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is omitted by not fully incorporating the variable of color into the system of homologies? Nijhout provides no specific answer to this question. Second, the plan is subjective in that there is no effort to quantify the similarities between pattern elements that lead to a hypothesis of homology. In general the lack of quantification in the description of pattern elements and in efforts to test Nijhout's ideas is notable.

The last chapter speculates on the impact of developmental or phylogenetic constraints and selection on the evolution of butterfly coloration. There are two key conclusions. First, many of the features of pattern elements (e.g., the shape of small elements such as parafocal elements) are probably not under direct selection and their evolution will be determined by what sort of pattern production mechanisms are available. This view seems plausible but highly speculative in that it broadly assumes interspecific similarity in the features of the visual system of predators and in the contexts of encounters. Second, the pattern-generating systems are so flexible that the evolutionary paths along which butterfly wing pattern may travel, driven by selection or other processes, are virtually limitless. This is good news for adaptationists whose hypotheses are often criticized for assuming few if any constraints on the trajectories evolution can take.

In summary, this book stands as a clear and current record of Nijhout's ideas and of his view of his and others' wo~k on the evolution and development of butterfly wing patterns. It is unique and of interest as a treatise on phylogenetic and developmental questions about these wing patterns. However, the reader must keep in mind that Nijhout presents only a single hypothesis for the inter- and intraspecific similarities in butterfly wing patterns and that the test of this hypothesis is incomplete. My hope is that researchers in this area will be stimulated by the challenge of generating and testing new sets of homologies as alternatives to the nymphalid ground plan.

RONALD L. RUTOWSKI, Department of Zoology, Arizona State University, Tempe, Arizona 85287-1501.

Journal of the LepidopteristS' Society 46(4), 1992, 307 -309

A FIELD GUIDE TO EASTERN BUTTERFLIES, by Paul A. Opler (illustrated by Vichai Malikul, with foreword by Roger Tory Peterson). 1992. Peterson Field Guide Series, No.4. Hough­ton Mifflin, Boston. xvii + 396 pp., 541 color paintings, 104 color photographs of living insects, and 348 range maps. Hardcover, 12 x 19 cm, ISBN-0-395-36452-3, $24.95; softcover, 11.5 x 18 cm, ISBN-0-395-63279-X, $16.95.

Was a new eastern field guide necessary? The total of 422 species described by Alexander B. Klots in his original guide in 1951 has expanded to 524 species, through the recognition of many more occasional immigrants and the addition of a few recently described species, minus a few species submerged to subspecies status. With this, and the acquisition of much new biological information, forty years was not too soon for an update.

The browser picks up this new field guide, turns to the color plates to see how the butterflies look, and sees-flowers! Thereafter follow three pages of photos of immature stages: first things first. And now nine pages, 68 superb photographs, of living butterflies doing what we most enjoy seeing them do: nectaring, basking, puddling. Their charac­teristic postures are clearly evident. Finally, on 35 color plates we see the expected formally sequenced, conventionally spread depictions of the great majority of the 524 species covered in the book, as color paintings ranging from superb (most of them), to barely adequate (only a few: i.e., in the genus Erynnis-but Erynnis are the betes noires of most lepidopterists).

By using this sequence, Opler is subtly emphasizing points made in his introductory chapters: the dependence of butterflies on their botanical substrates, and the fact that users of this book who wish to observe and photograph butterflies will greatly outnumber those who make collections of specimens. While acknowledging changing attitudes and

308 JOURNAL OF THE LEPIDOPTERISTS' SOCIETY

interests with regard to invertebrates, he does not in any way denigrate collecting. In fact, he describes in careful detail, with clarifying line drawings, the collecting and preservation of specimens, with emphasis on proper and purposeful collecting, and on responsible care of collections. The necessary information about butterfly anatomy, de­velopment, and behavior is well covered, as are rearing, gardening for butterflies, butterfly conservation, and in particular, life zones and butterfly habitats.

By whatever magic, Opler has succeeded in an area where his field guide predecessors were constrained: Klots with the original Field Guide to Eastern Butterflies, C. V. Covell with the Field Guide to the Moths of Eastern North America, and W. Tilden and A. C. Smith with the Field GUide to Western Butterflies. The illustrations of all the butterflies, even the black and white ones, are in color, thereby increasing the appeal and usefulness of the guide. And he has regained the benefits of "triple-indexing," e.g.: White, Checkered, Pontia protodice, protodice (Pontia). The reader accustomed to finding protodice in Pieris will nevertheless find the species readily in this index.

The color values, fine detail, and general gestalt of most of Malikul's paintings are magnificent. One could only wish that this were not a field gUide, so that all species might have been portrayed at life size. This, in fact, is the basis of a minor problem. It is immediately obvious that the stated scale for many plates must be taken with a grain of salt. In Plate 16, for example, at the stated scale of x 112, canadensis and glaucus are portrayed the same size, yet glaucus is rarely as small as canadensis and often is twice as large. On the same plate rapae is shown slightly larger than x '12 so that it seems almost to match the span of glaucus. And Plate 32, with various brushfoots, measures out at close to x '12, rather than the stated x 1. The caveat (Lepidoptera or no): go by the text, not by the scales!

This reader often approaches a new guide with an element of anxiety: "What names will they use this time?" Opler has opted for the conservative stance he employed in Butterflies East of the Great Plains (with George O. Krizek, 1984, The Johns Hopkins University Press, Baltimore, 294 pp.). He has even abandoned Polites coras in favor of P. peckius, familiar from Klots and from W. J. Holland (1898, The Butterfly Book, Doubleday, Page & Company, Garden City, NY, 382 pp.). But it was not an easy victory: Peck's Skipper is P. caras on Plate 13, P. peckius on Plate 44. When even the experts can get trapped in habit, it makes the dilemmas of nomenclature a little less tense for the rest of us!

The decision to avoid dwelling heavily on subspecies was a good one for a field guide to eastern North America, where subspecies rarely have sharply definable ranges. The "Life List" clearly points out which subspecies are actually found within the study area, and which of the nominate subspecies are extralimital. This, however, has introduced another minor problem. One would wish that the common name selected for each species were regularly that of the subspecies found within our area, such as American Copper (rather than Little Copper) for Lycaena phlaeas americana, or Tropical Buckeye (rather than Genoveva) for junonia genoveva zonalis. The most disconcerting subspecies problem arose with Evans' Skipper, Panoquina fusina evansi. It is properly described in the species account as having a "vague irregular white postmedian band." The plate, however, illustrates the nominate (extralimital) fusina, which bears a strikingly clear broad white band.

Species accounts are in the Klots (and Opler) tradition, covering color, pattern, shape, size, pleomorphism, and polyphenism. Similar species are compared; early stages, larval host plant, flight period are covered when known; diapausal stage is stated individually or by genus or large group, as applicable. This, coupled with the range (there are range maps for most resident species) and habitat information, provides a valid basis for searching for a species in the field, or identifying a specimen on film or in hand. A "remarks" section, for some species, gives significant behavioral and historical details. Genitalic details are not described, but their importance is stated for those species where they are critical for correct determination.

A recurring theme surfaces in the species accounts, as for example the following for Nastra lherminier, the Swarthy Skipper: "Early Stages: Not reported. Food: Little Blue­stem." This opens up a gold mine of opportunity for the amateur lepidopterist: the

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challenge of rearing, describing, and reporting early stages, so that the many lacunae in the knowledge of immatures can be gradually filled in. And for many other species Opler indicates that the larval host plant is still unknown. Field observations can provide the answers. Such information is essential for the understanding of the environmental re­quirements of threatened or endangered species.

There are scattered and sometimes confusing inconsistencies relating to diagnostic arrows, plate labels, and the explanatory captions accompanying the plates. A plate figure labelled as male may indeed be female, and properly described as female. Rarely a plate figure is unlabelled, or improperly labelled. A diagnostic arrow may point to a feature not referred to in the caption or species description, or an arrow may significantly miss pointing out the designated feature. Occasionally a range map may not coincide with the verbal account of the range. While these inconsistencies may at times be confusing to the novice, they usually can be worked out by careful comparison of the text in the plate caption with that in the species description. Such flaws are by no means insur­mountable and should be readily correctible in a second printing. Incidentally, the P;!latka Skipper (Euphyes pilatka) is not a typo: there probably was a slip-of-the-pen by W. H. Edwards in the mid-nineteenth century when he described the creature.

With the completion of the species accounts, the author devotes the remaining fifteen percent of the book to extremely useful accessory material. A "Life List" follows the sequence of the Miller and Brown list, except that the skippers are placed after the "true" butterflies, as in the body of the guide. There is a contingent benefit from this: the skippers present a challenge that the novice may prefer to defer. To have placed them first might have diminished the appeal of the book for some; swallowtails, on the other hand, are an immediate attraction. The list ends with a selection of nearly thirty "potentials," species almost reaching the covered area that have a good chance of wandering across the line, or of being accidentally introduced by the increasing agricultural commerce with the southern part of the hemisphere.

A copious glossary clarifies terms used in the introductory material and in the species accounts, making prior knowledge of lepidopteral terminology unnecessary for full en­joyment of the book. A list of references gives the reader access to general books on identification, butterfly biology and behavior, as well as state or more local coverages and checklists. The several very helpful books on butterfly gardening are not included, how­ever. There are extensive directories of organizations devoted to Lepidoptera, of suppliers of books and equipment, and of butterfly houses and insect zoos. The Collecting Guidelines formulated by The Lepidopterists' Society in 1982 constitute the final appendix. The indices, one for plants, one for butterflies, are exceedingly effective. The internal indexing between plate and text greatly simplifies use of the book.

In summary, the long-awaited and much-needed update of the Klots Field Guide is now here. Opler's species accounts, in the manner of those he pioneered in Butterflies East of the Great Plains, but necessarily condensed, provide the basic framework with which to establish acquaintance with any of the species of eastern butterflies, and from which to pursue further information, known and unknown. The live photos and Malikul's outstanding paintings reduce uncertainties to a minimum. This volume should become the standard resource for the study and enjoyment of eastern butterflies for the next several decades. It has been well worth waiting for.

WILLIAM D. WINTER, 257 Common Street, Dedham, Massachusetts 02026-4020.