436 Dr. Johnston on the British Aphroditacea. 



answers well also to Pallas's figure, but our worm is certainly 

 nothing more than a variety of the P. cirrhosa. Pallas, how- 

 ever, says that his Lepidota has only fourteen pairs of scales, 

 and were this point found to be correct, it would certainly de- 

 termine it to be a distinct species. We leave it to future in- 

 quiry. 



Polynoe cirrata, it seems necessary to remark, is not iden- 

 tical with the Aphrodita cirrhosa of Pallas, for he expressly 

 says that the bristles of the dorsal branch of the foot are 

 longer than those of the inferior branch. Misc. Zool., p. 96. 

 The species are otherwise very nearly allied. 



Plate XXII. Fig. 2. Polynoe cirrata, nat. size. 2 a. The head; 'the 

 antennse ; " the palpi ; '" the tentacular cirri. 2 c. A scale. 2 d. The 

 proboscis laid open. 2 e. A foot, with a tentacular cirrus. 2 /. A foot, 

 without the tentacular cirrus. 



3. P. impar, scales thirteen pairs, imbricate, rough ; tenta- 

 cular cirri clothed with short spinous filaments. Plate XXII. 

 fig. 3— 9. 



Hab. Under stones between tide marks. In Berwick Bay with the pre- 

 ceding, but rare. 



Desc. Body linear-oblong, narrowing insensibly from the 

 head to the tail, depressed, slightly convex on the back, of a 

 freckled or mottled brownish colour. Head concealed by the 

 anterior scales, square, sinuated in front, pale. Eyes very di- 

 stinct, the posterior pair most approximated. Proboscis with 

 four rather large corneous hooked maxillae, the orifice encircled 

 with a single series of simple filaments. Antenna five, the 

 central one setaceous, elongate, of a pink or flesh-colour ; the 

 middle pair very small ; the outer pair as long and rather 

 thicker than the odd one, but pale-coloured, all of them ap- 

 pearing roughish when highly magnified. Scales thirteen 

 pairs, imbricate, covering the back entirely, some of them 

 roundish, others subquadrangular, and others kidney-shaped, 

 rough with miliary granules excepting on the covered side, 

 the external margin fringed with short cilia. Feet uniramous, 

 armed with two fascicles of very stout bristles, the superior with 

 the most numerous and longest bristles. Bristles all of them 

 simple, the longest formed like a lance, the shorter curved like 

 a sword towards their points, which are concave and serrulate 



