174 NE W YORK STATE MUSEUM 



Famil 



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 lunifrons 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 

 ^i&^fr;^' large and truncate. Inner branch of 



,4^,; i^ < S0L uropoda pointed and reaching tip of 



ftSp^^^^^^^V^slI J abdomen, outer branch one fourth 

 ^^g^^^^S^ir^:<? ' longer than inner. Legs short and 



equal. 



Found below high water mark in 

 muddy situations, clinging to the 

 Fi _ r underside of boards and bark. 



rig. 45 Cassidina lunifrons 



Usually covered with mud so that 

 its color can not be recognized. 



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

 brown and blackish spots. 



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



Sphaeroma quadridentatum Say 



S p h a e r o m a quadridentatum Say, T. Acad. Nat. Sci. Phila. 

 Jour. 1818. 1:400. Verrill. /. c. 1874. P-569- Harger. /. c. 1880. p-368, 

 pl.9, fig.53-54. Richardson. /. 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. 



