Dr. P. P. Carpenter on new Forms of ^fuUusks. 45 



large, obtuse, conical protuberance, slightly curved upwards, 

 that extends considerably b^ond the spinners ; it has a bright 

 silver)' lustre ; a black band extends along the middle of the 

 upper part to the posterior conical protuberance, and is crossed 

 at its anterior extremity by a broad strongly cur\ed black band, 

 within whose cur>ature there is a short transverse line of the 

 same hue; on each side of the medial band a shorter, nearly 

 parallel black band occurs ; these bands, which commence near 

 the extremities of the curved band, are connected anteriorly by 

 a transverse black bar, laterally by four oblique lines of the 

 same hue, diverging in pairs from the medial band, and poste- 

 riorly by converging till they meet ; irregular longitudinal bands 

 and short oblique streaks on the sides, and a space round the 

 spinners, have a black hue, the last comprising four silvery spots 

 disposed symmetrically about the spinners ; the sexual organs 

 are moderately devcloned, and of a dark reddish-brown colour, 

 that of the branchial o|)ercula being yellowish brown. The 

 ■cepbalothorax is small, slightly convex, glossy, compressed be- 

 fore, rounded in front and on the sides, with a large indentation 

 in the medial line ; the falces are short, powerful, very convex 

 in front, rather divergent at the extremity, and armed with a 

 dark, red-brown fang, and a few teeth on the inner surface ; the 

 maxilla; are divergent, and increase in breadth from the base to 

 the extremity, which is somewhat angular on the outer side ; 

 the sternum is heart-shaped, with small pr< ^ on the 



sides, opposite to the legs ; the legs are long, . and pro- 



vided with liairs and spines: those of the specimens from which 

 the description was made were mutilated ; but, from the relative 

 length of the femora, it is evident that the first pair is the 

 longest, then the second, and that the third pair is much the 

 shortest ; the palpi are short and slender. These parts have a 

 yellow-brown colour. The lij) is semicircular and prominent at 

 the apex, which has a yellow-brown hue, that of the base being 

 dark brown. The eyes arc nearly equal in size, and are seated 

 on black spots on the anterior part of the cepbalothorax ; the 

 four intennediatc ones form a square, and those of each lateral 

 pair (which are placed on a minute tubercle near to each other, 

 but not in contact) are rather the smallest of the eight. 



V. — Diagnoses of new Forms of MoUusks collected at Cape 

 St. Lucas by Mr. J. Xantus. By Philip P. Carpenter, 

 B.A., Ph.D. 



[Concluded from vol. xiii. p. 4/9.] 



37. Mangelia subdiaphana, 



M. testa par^a, subdiaphana, albida, interdum rufo-fusco pallide 



