270 REPORT OF NEW JERSEY STATE MUSEUM. 



Description. — Body oval, broad, with smooth surface. Head 

 broader in front than behind, and anterior lateral angles pro- 

 duced in lateral direction and form very acute angles. Eyes 

 placed at posterior lateral corners of head. First antennse reach 

 two or three joints beyond antero-lateral angle of head, and 

 flagellum with six joints. Second antennse reach hind edge of 

 first thoracic segment, and flag'ellum with about eight joints, of 

 which first four large and last four small and setose. First 

 thoracic segment well fitted to head, to form elliptical body con- 

 tour. Segments subequal, with straight lateral edges. Epimera 

 not distinct from segments. First abdominal segment short, and 

 subtriangular segment with truncate apex. Uropoda with inner 

 branch pointed at end, and reaches tip of abdomen. Outer 

 branch of uropoda rudimentary, about one-fourth length of inner 

 branch. Color brownish above, paler below. Length i mm. 



Remarks. — ^Known only from Great Egg Harbor, where it 

 was collected by Dr. William Stimpson. It is closely related to 

 Cassidisca ovalis (Say) from South Carolina, and may ulti- 

 mately prove identical. Only the type and Paulmier's examples 

 known until Mr. E. G. Vanatta secured numerous specimens at 

 Chestertown in Maryland, in November, 19 12. They were found 

 along- the banks of the Chester River. 



Family ANCINID^ 



Body oval, depressed, short, convex. Head broadly trans- 

 verse. Abdomen formed of two segments, and first formed 

 by fusion of several segments. First and second antennse multi- 

 articulat^, with peduncle and flagellum distinct. Mandibles with 

 palps. Uropoda lateral, and with terminal abdominal segment 

 fomi caudal fan. Outer branch of uropoda entirely absent, and 

 inner branch immovably fixed. Epimera united with thoracic 

 segments. First and second pairs of legs subchelate, others 

 ambulatory. 



A single genus. 



