264

Noveinher 1 1, 185 1.

W. J. Broderip, Esq., Vice-President, in the Chair.

Professor OWEN read a paper “ O n the Capacity of the Cranium in the Negro, the Orang, and the Gorilla,” which will be published in the Transactions of the Society for the present year.

The following papers were also read :-

1 . DESCRIPTIONS OF SIXTEEN NEW SPECIES OF RISSOINA, A GENUS OF MARINE GASTEROPODOUS MOLLUSKS, FROM THE CUMINGIAN COLLECTION. BY ARTHUR ADAMS, SURGEON R.N.,F.L.S. ETC.

RISSOINA, D’Orbigny. About eighteen species of this genus, as restricted by M. #Or-

bigng, have been already described, inhabiting various countries. Those here iianied are a portion of the discoveries made by Mr. Cu- niing among the islands of the Philippine Archipelago, and are many of them of considerable size ; and it is in these that the peculiarity of operculum is bebt seen.

The process of the semiovate, horny, subspiral operculum, first pointed out by D’Orbigny, is sometimes very long and slender, and very much resembles in appearance the analogous appendage of the operculum of Nerita and Neritina. The genus Jefreysia of Alder, or Rissoella of Gray, has a similar appendage, but the position of the eyes, and the peculiar structure of the fore part of the head, place the latter genus in a different family, viz. Pyramidellide. The &issoin@ may also readily be known from the neighbouring genus Rissoa, by the aperture being somewhat channeled anteriorly, whereas in Rissoa it is continnous and entire. The nature of the animal re- sembles Rissoa, according to D’Orbigny, who places the genus among the Melaniada.

1 . RISSOINA PLICATA, A. Adams. R. testd turrito-subulatd, subpyramidali, albd, sordidd, anfractibus octo, planis, longi- tudinaliter valdk plicatd, transoersiin striatd, plicas elevatis, postick subangulatis, interstitiis transversim striatis ; aperturd semiovatd, antic2 s u b c a n a l i ~ u ~ a t ~ ; labro antic2 subdilatato, margine incrassato.

IZab. Isle of Masbate.

2. RIPSOINA FASCIATA, A. Adams. R. testd subulato-turritd, solidd, sordid2.a16d, rufo-fusco Jasciatd, anfractibus octo, con- vexiusculis, transversiin tenuissimk (sub lente) striatd, longitu- dinaliter plicatd, plicis obliquis, aqualibus, subdistantibus; apwturd semiovatd, antic? subcanaliculatd ; labro subdilatato.

Mus.

Mus. Cuming.

Hub. Sydney, under stones, low water (Mr. Stranye). Curning.

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3. RISSO~NA SCALARIANA, A. Adams. 11. testd subulato- turritd, albd, solid&, anfractibus octo, convexiusculis, trans- versim tenuissim2 striatd, longitudinaliter eostatd, costis ele- vatis, aqualibus, subdistantibus, anfractu ultimo antic2 callo circumdato ; aperturd serniovali, antic2 subcanaliculatd; labio antic2 callo desinente ; labro $exnoso, antic2 subproducto.

Jfab. Isle of Burias, Philippines.

4. RISSOINA PYRAMIDALIS, A. Adams.

Mus. Cuming.

R. test& t u w i t o - p y a - midali, sordid2 albd, solidd, anfractibus oeto, planiusculis, transversim tenuiter striatr?, longitudinaliter plicatci, plicis obliquis, con fertis , subelevatis, interstitiis transversim striatis ; aperturd semiovatd, antic? subcanaliculatd; labio antic2 call0 desinente ; labro subdilatato, incrassato.

Hab. Isle of Baclayoe. Mus. Cuming.

5. R~SSOINA D’ORBIGNYI, A. Adams. R. testd subulato-tur- ritd, albidd, subpellucidd ; aqfiactibus decem, convexiusculis, secpremis costellatis, lineolis elevatis, transversis, et longitudi- nalibus, decussatd; aperturd semiovatd, antic2 subcanaliculatd ; labio antic2 subcalloso ; labro dilatato, subreflexo, margine flexuoso, subacuto.

Ha6. Isle of Luzon. Mus. Cuming.

6. RISSOINA CLATHRATA, A. Adams. R. testa” sulrulato-turritd, albd, solidd, anfractibus convexiusculis, lineis elevatis, longi- tudinalibus et transversis decussatis, valde clathratif, anfractu ultimo antic2 sulco transverso instruct0 ; aperturd semiovatd, anticb subcanaliculatd; labroflexuosoy anticb producto, margine extus varicoso.

Z a b . Isle of Bohol.

7. RISSOINA MICANS, A. Adams. R. test4 turrito-subulatd, albd, solidd, nitidd, anfractibus convexis, novem, Longitudi- naliter plicatdY pL@ elevatis, subdistantibus, aqualibus, in- terstitiis transverszm striatis, anfractu ultimo antic2 valde sulcato ; aperturci semiovatd, antic2 subcanaliculatd ; labro jlexuoso, antic2 subproducto, extus varicoso.

Mus. Cuming.

Hab. Island of Mindanao.

8. RISSOINA NIVEA, A. Adams.

Mus. Cuming.

R. testd parvd, sulrulato-tur- ritd, subpellucidd, nived, subnitidd, anfractibus convexiusculis, longitudinaliter plicatd, plicis obliquis, antic2 subobsoletis ; aperturd semiovatd, antic2 subcanaliculatd ; labro subdilatato, extus incrassato.

Hab. Port Lincoln, Australia.

9. RISSOINA MONILIS, A. Sdams. It. testd turrito-subulatd, solidd, f u l v d , anfractibus septem, planis, granulis monilayor- mibus ad suturas, longitudinaliter plicatii, plicis conferkis, an- yustis, aqualibus, interstitiis punctato-clathratis ; aperturti

Mus. Cuming.

2GG

semiovatd, antic2 subcanaliculatd ; labio subincrassato ; labro extus valde earicoso, margine transversim striato.

Hab. Philippine islands. Mus. Cuming.

10. RISSOINA BELLULA, A. Adams. R. testd subulato-turritd, albd, sernipellucidd ; anfractibus octo, convexiusculis, cingillis transversis, elevatis, granulosis, interstitiis longitudinaliter concinnb clathrutis, ornatd ; snfractu ultimo sulco profundo instructo ; aperturd semiovatd, antic2 subcanaliculatd ; labio antic2 callo terminato ; labro jZexuoso, margine extus valde varicoso.

UaB. Isle of Calapan.

11. RISSOINA STRIOLATA, A. Adams.

Mus. Cuming.

R. testd subulato-turritd, albd, tenui, pellncidd ; anfractibus undecim, supremis longi- tudinaliter plicatis, planidatis, prope suturas subangubatis ; transversim striatd, striolis confertis concentricis ; aperturd semiovatd, antic2 subcanaliculatd ; labio pos t id incrassato, an- tic2 callo desinente ; labro dilatato, margine incrassato, sub- refexo.

I€ab. Baclayon island, Philippines.

12. RISSOINA COSTATI, A. Adams.

Mus. Cuming.

R. testd subulato-turritd, albd, opacd, solidd, anfractibus septem, convexiusculis, longi- tudinaliter costatd, costis crassis, elevatis, posticb mbanyula- tis, anfractu ultimo antic? sulco transverso valid0 instructo ; aperturd semiovatd, antic2 subcanaliculatd ; labio antic2 tuber- culo terminato ; labro subdilatato, margine varicoso, Jlexuoso.

I€ab. Cobiga, Peru. Mus. Cuming.

13. RISSOINA NITIDA, A. Adams. R. tesfd turrito-subulatd, alba", solidd, nitidti, anfractibus novem, convexiusculis, lonyi- tudinaliter costatd, transversim liratd, liris ad costas nodu- losis ; aperteird seniiovatii, antic2 subcanaliculatci!; labio antic2 callo desinente; labro extus incrassato, margine subacuto, antic; diaphano producto.

Hab. Isle of Camaguing.

1.2. RISSOINA CONCINNA, A. Adams.

hlus. Cuming.

R. test6 subulato-turritd, alhd, solid&, ' ~ ~ i f i d d , anfractibus septem, planiusculis, Zongitu- dinaliter plicatd, plicis antic2 evanidis, transversim striatd, striis creberrimis, confertis ; aperturd semiovatd, antic2 sub- canabiculatd; labio calloso ; labro margine valde incrassato e t rotundato.

Hub. Cagayan, Philippines. Mus. Cuming.

15. RISSOINA NODICINCTA, A. Adams. 12. tesfd subulato-tur- ritd, albd, solidd, anfractibus 10-1 2, convexis, longitudinaliter plicatd, plicis an,qustis, distantibus, transversim tenuissimb stri- atd, in medio anfractuum ciqquld elevatii ad plicas nodosd, or- na fa, sictnrl? tiorlidis m o , r i I ~ ~ f b n n i l i r ~ ~ cilicti; aprturii! semiovatfi,

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antic2 subcanaliculatd; labio antick callo terminato; labro dila- tato, extus incrassato, marginejlexuoso.

Hab. Isle of Capul, Philippines.

16. RISSOINA CCELATA, A. Adams. R. testd subulato-turritd, albidd, solidd; anfractibus octo, convexiusculis, supremis cla- thratis, ultimo cinyulis elevatis, cequalibus, subdistantibus, transversis, interstitiis lineis elevatis, longitudinalibus e t trans- versis, decussatinz ornato ; aperturd semieUipticd, antic2 sub- canalieulatd; labio calloso ; labro antic2 dilatato, margine in- crassato, subrejlexo.

Mus. Cuming.

Hab. Siquijor. Mus. Cuming.

The two following species are true Rissoa, characterized by the simple aperture, which is not channeled in front, aud by the absence of the calcareous appendage to the operculum. Many species of small shells have been inaccurately referred to Rissoa, some of which belong, however, to entirely different families.

R i s s o A BELLA, A. Adams. R. testa" turrito-subulatd, alhd, solidd; anfractihus quinque, planiusculis ; spird apice obtuso, lineis transversis, elevatis, concentricis, confer tis, ornatd ; aperturd ovali, antic2 integrd; labio subcalloso ; labro sub- dilatato, extus marginato, margine jlexuoso.

Hab. Philippine islands. Mus. Cuming.

RISSOA ELEGANS, A. Adams. R. testd subulato-turritd, albil, sem+ellucidd; anfractibus 7, convexiusculis; suturd canalicu- Eatd, lineis elevatis transversis concentricis et longitudinalibus concinn2 decussata"; aperturd ovali, sUbprOdUCta, antic2 inte- grd; lahio calloso; labro antic2 dilatato, extus varicoso, mar- gine acuto, subrejexo.

Hab. Philippines. Mus. Cuming.

2 . DESCRIPTIONS OF SEVERAL NEW SPECIES OF MUREX, RIS- SOINA, PLANAXIS, AND EULIMA, FROM THE CUMINGIAN COLLECTION. BY ARTHUR ADAMS, F.L.S. ETC.

1. MUREX IOSTOMUS, A. Adams. M. testd ovato-fusiformi; spira" acuminatd; anfractibus planulatis, squamulosis, spinis acutis, in serie elevato disposito ornatis, cinered; anfractu ul- timo spinis elevatis, bz>dis, in seriebus quatuor dispositis in- structo, varicibus sex, longitudinalibus ; aperturd ova fo-oblongd, intus aiolaced; labio subtuherculari; labrojmbriato.

Hab. Philippines. Mus. Cuming.

2. MUREX s o L i m s , A. Adams. M. testd solidd, profund2 um- bilicatd, albd; spird brevi, obtusd; anfractibus planulatis, lon- gitudinaliter plicato-varicosis (varicibus in anfractu ultimo 7), transversim liratis ; &is, ad plicas, incrassatis, interstitiis lon-