110 APHRODITACE.*. 



bricate, rough with brown granulations, cihated on the external mar- 

 gin, the overlapped smoother than the exposed portion, for the 

 granules on the former are more minute than on the latter ; the 

 anterior scales are smaller and rounder than the others, and com- 

 pletely cover the head, which is a subtriangular pink or purplish 

 corneous plate, furnished with four small eyes : antennae three, the 

 central one largest, bulbous near the point : palpi two, longer than 

 the antennae, swollen near the apex ; the tentacular cirri similar to 

 the superior cirri of the feet ; these are white, with a blackish ring 

 at the bulb where the acumination commences, retractile, originating 

 from above the dorsal branch of every alternate foot and under the 

 scales ; the last three pairs of feet each with a cirrus : feet twenty- 

 five pairs, obtuse, sub-bifid, the dorsal branch shorter and less than 

 the ventral, each terminated with a brush of stiff brown bristles, and 

 under the ventral branch there is a small setaceous cirrus and also a 

 fleshy spine at its junction with the belly : bristles when removed 

 golden-yellow, those of the dorsal branch slenderest, gently curved, 

 pointed, and serrulate for about half their length ; those of the ven- 

 tral branch stouter, slightly bent near the top, and serrulated with 

 a double series of teeth on the outer side of the bend ; they are 

 similar to those of L. clava ; each tuft of bristles enclosing a dark 

 brown straight spine, the inferior stouter than the upper one : ventral 

 surface straw-colour, prismatic, marked with the viscera, and some- 

 times spotted with black near the base of the feet. 



This species differs remarkably from those which follow in the 

 tenacity with which the dorsal scales adhere to their tubercles of 

 attachment, from which they cannot be separated except by the 

 dissecting-knife ; and this fact determines the species to be almost 

 certainly the Aphrodita squamata of Linnaeus. His Aph. scahra 

 must ever remain in uncertainty, for no Polynoe has twenty scales, 

 as he states them to be in that species. The Aph. scahra of Otho 

 Fabricius is said to have fifteen pairs of scales ; and overlooking this 

 important fact, I, on a former occasion, much too confidently identi- 

 fied it with the present ; but the description is otherwise so very 

 applicable, that, I must acknowledge, a suspicion of there being the 

 same species still remains*. That this is the Aph. scabra of British 

 authors scarcely admits of a doubt. It is much less certain whether 

 it is the Aphrodita clava of Montagu ; but as he has himself sug- 

 gested their possible identity, and as his description and figure are 

 both of them too imperfect to characterize a species, we see no harm 

 in reducing his to a conjectural synonym. In the description, the 

 scales are stated to be "twelve or thirteen pairs," but the figure 

 shows thirteen scales on one side and fourteen on the other, with a 

 naked space between the rows. Audouin and M. -Edwards conjecture 

 that Aph. clava may be the same as their Polynoe Icevis, characterized 

 by having fourteen pairs of perfectly smooth scales. 



* Under the name of Aphrodita squamata, Sir J. G. Dalyell figures a specimen 

 (Pow. Great, ii. 166. pi. 24. f. 3) about 2^ inches long, and nearly one in breadth, 

 which has " about thirteen pairs of scales." In the figure, fifteen pairs are repre- 

 sented, and it is very probably the Aph. scabra of Fabricius. 



