274 BULLETIN 54, UNITED STATES NATIONAL MUSEUM. 



Color, brown. 



Specimens were found at Great Egg Harbor, New Jersey, by Dr. 

 William Stimpson. 



Type, Cat No. 4402, U.S.N.M. 



This species is very similar to the following one, and may prove to 

 be the same. As the type and only specimen of Say's species is in 

 such a bad state of preservation, I am unwilling as yet to identify this 

 species with it. 



CASSIDISCA OVALIS (Say). 



Nsesa ovalis SAY, Jour. Acad. Nat. Sci. Phila., I, 1818, pp. 484-485. RICHARD- 

 SON, American Naturalist, XXXIV, 1900, p. 224; Proc. U. S. Nat. Mus., 

 XXIII, 1901, p. 537. 



Locality. South Carolina. 

 Depth. Found on surface. 



"Body oval, depressed; ultimate segment of the tail obtuse, with 

 three hardty raised, very obtuse lines at base; lateral appendices 

 dilated, three caudal segments. 



"Inhabits bays and inlets of the United States; common. Cabinet 

 of the Academy. 



" Body perfectly oval, segments subequal, fourth, tifth, and sixth 

 largest, first segment of the tail equal to the- 

 preceding one, simple; terminal segment tri- 

 angular, obtusely rounded at tip, rectilinear 

 each side, half as long as the body, with three 

 longitudinal, abbreviated, raised, very obtuse 

 lines at base, of which the middle one is most 

 FIG. 285. CASSIDISCA OVALIS. conspicuous; lateral processes dilated, de- 

 ABDOMEN- WITH UROPODA. presse( ^ rectilinear within and rounded on 



the external margin, so as to form with the 



terminal segment a perfectly semiorbicular termination of the body, 

 without interval; head somewhat unequal; e} r es conspicuous, hemi- 

 spherical; antennas equal; labrum triangular, advanced, very conspic- 

 uous, terminating the head before and forming, with the base of the 

 superior antennae behind it, a rounded termination without interval, 

 completing the oval form of the body; feet all armed with bifid nails, 

 none of which close on the preceding joint. 



"Length less than three- twentieths of an inch. 



"This little animal is extremely common in sea w r ater, usually 

 creeping on fuci and other marine plants; we found it as far south as 

 St. Johns River in Florida." SAY." 



A dried specimen, mounted on a pin, the type and only specimen of 

 this species is in the Philadelphia Academy of Natural Sciences. The 

 specimen was loaned me for examination. 



ajourn. Acad. Nat. Sci. Phila., I, 1818, pp. 484-485. 



