.

11. Remarks on Scobptndra elrBrica, and Sc. fubtcrranea. By Grorge Sbw, M. D. F. R. S. and L. S.

Read April 7, 1789..

MONGST the Englifh infells of the genus &olopcn&a A there appears to me to exiit a fpecies which is not diftinfily defcribed, and I believe is generally confounded with the Scolopendra cleBricu of Linneus, which it fo much refembles that it is not eafy to give a criterion by which it may at all times be diltinguifhed from it. The mofi firiking difference, as t o its external appearance, confifts in its being of a much lighter colour than the Scohpcndr~ eZc~9ricrr; the clc&lricu being of a full brown, or approaching to a chefnut colour, while this other fpecies is ncver much deeper than a ftraw colour. Another diitinAive mark is, that it is nar- rower and thinner in proportion than the cleHrica; and though I have never accurately counted the number of feet, yet I am itrongly inclined to think that they are more in number than thofe of the clearica. But what kerns mofi to indicate-a difference of f’cies is the very different habitation of this infeLCt; for while thc Sc. clcEtricn is found in houfes, and amongit wood, linen, and other fubitances, thc fpecies or variety I am now fpenking of is never found any where but at a confiderable depth beIow the furface of the ground, and principally refides in garden ground, in which it may be generally found about.the roots of plants at moit kafons of the year, except in very frofiy weather. If placed. in a dry box it will fccarce furvive more than a finrle L> day, and fre-.

(1 u e 11 tl y

8 DR. SHAW’S Remaris on

quently not fo long. On the contrary, the clc&lrica may be always preferved in this manner at leait a month, and frequently two or three months together, without feeming to lofe much of its vigour; nay, it may even be kept pretty clofely confir,ed between two glafles for rnany days without any danger of periihing.

Another very curious particular belonging to the Sc. E ~ C -

trica (and which cannot be obferved in the other fpecies) is, that if cut in two about the middle, both parts will live and appear vi- gorous for a very confiderable time; fometimes a fortnight ; but with this very extraordinary circumfiance, that the tail-part always furvives the head-part two or three days; fo that the principle of vitality is much more powerful in the lower part of the creature than in the upper.

T h i s experiment I made and frequently repeated feveral years ago, and till lately imagined that it had not been obferved by any other pcrfon ; but I lately obferved a remark by Haller in his Bibliothrca Anatmica, that the circumfiance of both the cut parts living has been mentioned in a German work entitled Unscr’s Kleinc Scbrifttm. This being a work I have never feen, I can only quote the very brief exprefion of Hailer, viz. ‘‘ Scolopendre diffe&z utraque ‘6 mcdietas vixit:” yet there is no mention of the poiterior part furviving the anterior, nor is the particular fpecies of the infea mentioned.

I am aware that it may be objec9ed to the idea of thefe two forts of Scolopcndra being i‘pecifically different, that the different habita- tioil of thc animal, and a difference in colour, are not fufficient to confiitute a difference of fpecies, efpecially as fome animals are fuppofed to refide in habitations of the greaten poifible difference; the Fizfiiola btpat;ca for infiance, which is fuppofed to inhabit the waters, and yet is found in great abundance and in great vigour in the liver and gall-bladder of fheep: It is all0 a well-known

circum-

circumfiance, that the larva: of many infeAs are fubkrraneous, while the infe&s in their complete ifate inhabit the furface. Yet with r d p & to the two Istolopcdrce before mentioned, I muit ifill think that them are fufficient grounds for fuppofing a real axid fpecific difference; and in order that they may the more eafily be difinguiihed, it might not perhaps be improper to give to thefpe- cieE thus imperfeEtly defcribed, the trivial name of fubtcrruncu.

I am by no means certain that the Sc. fibterramu yields any of that phofphoric light which prevails fo itrongly in the other: fhould this be uniformly the cafe, there is itill another argument in favour of a real iptcific difference.

VOL. IL C 111. Remarks