18 NEW-YORK FAUNA — CRUSTACEA. 



GENUS HIPPA. Fahricius. 



Body oblong-oval, convex, truncated in front, with a small triangular rostrum. Tail short, 

 with a lamellar appendix on each side of its base. Hands without pincers, compressed, 

 oval. External antennae usually rolled up, but, when extended, long and filiform, with a 

 double series of long hairs. Tarsus of the second and third pairs of feet lunated ; of the 

 fourth, triangular. 



HiPPA TALPOIDA. 



PLATE VII. FIG. 17. 



Hijipa lalpoida. Say, Jour. Acid. Nat. Sciences, Vol. 1, p, 160. 



H. emerila ? MiLNE-EDWiRDS, Hist. Nat. des Crust, Vol. 2, p. 209. Godld, Ioc. cit. p. 328. 



Description. Shield with interrupted rugous lines in front, smooth behind. Tail more than 

 half the length of the shield, sublanceolate, with reflected lateral margins ; the external 

 spine of the large basal articulation of the external antennaj extends somewhat beyond the 

 globular part of the fourth articulation. Body convex-oval when the tail is inflected upon it, 

 concave above, on the sides, in front, and very convex behind. Immediately behind the ros- 

 trum is a deep transversal furrow 0'25 in length, its end turned slightly backwards ; a similar 

 furrow, but curved with its concavity forwards, and with a smooth elevated margin, is placed 

 somewhat in advance of the central portion of the thorax. Rostrum small, triangular, with 

 a deep emargination on each side, terminated by a small tooth exceeding somewhat the ros- 

 trum. External antennas longer than the shield, but frequently folded up, and almost entirely 

 concealed between the mouth and the external jaw-feet. Eyes very small, on filiform pedi- 

 cels. Internal antennae short. Tail pointed with a double series of hairs. Terminal articu- 

 lation of the anterior feet oval. 



Color, light reddish brown ; the shield purple. 



Total length, excluding the antennre, 2* 0. Transverse diameter, 0-6. Tail, 0'6. 



The original describer of this species, Mr. Say, stated that it was very closely allied to the 

 H. emerita of authors ; but was of opinion that the great length of the antennae, and the shape 

 of the tail, indicated a distinct species, Milne-Edwards has, however, in the work cited above, 

 referred it with doubt to the H. emerita, and in this he is followed by our distinguished crus- 

 taceologist Dr. Gould. In his description of the //. emerita from Brazil, M. Edwards says, 

 " L'epine externe du grand article basilaire des antennes externes, depassent de beaucoup 

 " la portion globuleuse formee par le quatrieme article pedonculaire de ces organes." An in- 

 spection of the magnified figure on the plate, will show that the foregoing phrase does not 

 apply to this species. 



This species is known under the popular name of Sand-bug, and burrows in the sand be- 

 tween high and low-water mark. The ease and rapidity with which they burrow, has given 

 rise to its trivial name. They are occasionally used as bait. It occurs along the coast of the 

 United States, from near Cape Cod southwardly. 



