i74 



NEW YORK STATE MUSEUM 



Family sphakromidae 



Body short and convex. Head broad and transverse. Anten- 



nulae and antennae multiarticulate and distinctly divided into 



peduncle and flagellum. Anterior segments of pleon short with 



segments united. 



Cassidina lunifrons Richardson 



Cassidina 1 u n i f r o n s Richardson. Am. Nat. 1900. 34:222. U.S. 

 Nat. Mus. Proc. 1901. 23:533. fig. 14. 



A small species with broad, elliptic 

 body. Head broader than long and 

 set into thorax, eyes at posterior 

 lateral corners. Terminal segment 

 large and truncate. Inner branch of 

 uropoda pointed and reaching tip of 

 abdomen, outer branch one fourth 

 longer than inner. Legs short and 

 equal. 



Found below high water mark in 

 muddy situations, clinging to the 

 underside of boards and bark. 

 Usually covered with mud so that 

 its color can not be recognized. 



Length 1 mm. Color yellowish brown with many small, dark 

 brown and blackish spots. 



Taken at Bartow and at Fresh Kills, S. I. 



Sphaeroma quadridentatum Say 



Sphaeroma quadridentatum Say, T. Acad. Nat. Sci. Phila. 

 Jour. T818. 1:400. Verrill. /. c. 1874. p. 569. Harger. I. c. 1880. p.368,. 

 pl.9, fig.53-54. Richardson. I. c. 1901. p.533. 



A littoral form which may be distinguished from other marine 

 Isopoda by its habit of rolling itself up into a round ball when dis- 

 turbed, like the land " pill-bugs ". Body broad and elliptic. Ter- 

 minal segment rounded, branches of uropoda subequal and extend- 

 ing beyond tip of terminal segment. 



Found on the underside of rocks, between tides. 



Fig. 45 Cassidina lunifrons 



