172 SMITHSONIAN MISCELLANE:0US COLLECTIONS 



277. DROMIDIA EXCAVATA Stimpson 



Dromidia excavata Stimpson, Proc. Acad. Nat. Sci. Phila., x, p. 239 

 {77], 1858. 



The following description was taken from a young female speci- 

 men. The body and feet are covered with pubescence which is 

 longest beneath. Carapax smooth, strongly and regularly convex, 

 ■equally so anteriorly as posteriorly. The sides are nearly parallel, 

 so that it has a quadrate appearance, were it not for the protrusion 

 •of the front. The sides of the carapax below the sulcus, where pro- 

 tected by the retracted feet, are membranaceous. This is probably 

 a mark of immaturity. The subhepatic regions are deeply excavated 

 in front. Front small, bifid as seen from above, but with a smaller, 

 slender, curved, acute, median tooth below ; tooth over eye peduncle 

 small, external orbital angle not dentiform. No teeth on antero- 

 lateral margin except that forming the external angle of the hepatic 

 excavation and that at the deep lateral sulcus. The anterior margin 

 ■of the meros-joint in the external maxillipeds is oblique and the ex- 

 ternal angle obtuse. Chelipeds small, angular, but with smooth sur- 

 faces ; carpus protuberant and with a strong superior tooth ; hand 

 without teeth ; fingers compressed nearly as long as the palm. Hair 

 on the outer side of the hand dense, arranged in longitudinal lines. 

 Ambulatory feet of moderate length, fifth pair longer than the 

 fourth. Abdomen of the female with an obtuse carina. On the in- 

 ferior surface of the body the thick, hairy covering is excavated in 

 numerous pits or concavities, at the bottoms of which the protuber- 

 ant parts of the abdomen and foot-bases appear, almost bare of 

 pubescence. Color brownish ; fingers of chelipeds pale crimson. 

 Length of carapax, 0.37 ; breadth, 0.35 inch. 



In our specimen, which is evidenth' a young one, the copulatory 

 sulci are indistinct, and produced only to the fifth sternal segment. 



It was found among soft sponges dredged in six fathoms, on a 

 muddy bottom, in Port Jackson, Australia. 



Genus CRYPTODROMIA Stimpson 



This name has been proposed for a group of small species which 

 are very numerous in the East Indian and Pacific seas. They are 

 littoral in their habits, and always found concealed in some foreign 

 living body, generally a compound ascidian. They are easily recog- 

 nized by their size and aspect, being small, subglobular, and covered 

 with a very short pubescence only. The carapax is generally a little 



