ISOPODS OF NORTH AMERICA. 



401 



Fig. 448.— Erichsoxella at- 

 TEXUATA (After Hak- 



GER). X 3. 



than the second. The tir.st i)air of antenna' extend to the middle of the 

 third article of the peduncle of the second ])air of antenna'. The Hrst 

 article of the second antenna' is short and inconspicuous in a dorsal 

 view; the second article is long, about three times lono-er than the lirst; 

 the third is about one and a half times longer 

 than the second; the foui'th is about one and a 

 half times longer than the third; the fifth is a 

 little shorter than the fourth. The flagellar ar- 

 ticle is a little longer than the fourth peduncu- 

 lar article. The second antennie are 7i mm. 

 long, or longer than half the en- 

 tire length of the body. The palp 

 of the maxillipecls is composed of 

 four articles. 



The lirst segment of the thorax 

 is a little shorter than any of the 

 others except the seventh, both of 

 which are 1 mm. long. The sec- 

 ond, third, fourth, and lifth seg- 

 ments are subequal and each is 



about 1^ mm. in length. The sixth segment is about li 

 mm. long. The epimera are distinctly separated on all 

 the segments, including the first. They are very small, 

 almost inconspicuous, placed in the, first three seg- 

 ments on the lateral margin anterior to the median trans- 

 verse line. In the fourth segment thej" occupy the middle of the lat- 

 eral margin. In the last four segments they are placed below the 

 median transverse line. They give the segments a rather angular 

 appearance. 



The abdomen is composed of a single segment. About one-third 

 the distance from the base to the posterior extremitv is a small lateral 

 process on either side. Below these processes the sides of the al)do- 

 men are nearly parallel to a point about i nun. from the extremity, 

 where they converge to a rounded apex. 

 The legs are all ambulatory with bi-unguiculate dactjTi. 



ERICHSONELLA FILIFORMIS (Say). 



Stenosoma filiformls Say, Jour. Acad. Nat. Sci. Phila. , I, 1818, p. 424. — Milne 

 Edwards, Hist. Nat. Crust., Ill, 1840, p. 134. 



Idotea filiformis Vt^ HiTE, Hist. Crust. Brit. Museum, 1847, p. 95. 



Erichsoniu Jiliformit Hakger with Verrill, Report U. S. Commissioner of Fish 

 and Fisheries, 1873, Ft. 1, p. 570 (276); p. 316 (22).— Harger, Proc. U. 8. 

 Nat. Mus., II, 1879, p. 160; Report U. S. Commissioner of Fish and Fisher- 

 ies, 1880, Pt. 6, pp. 355-356, pi. vii, figs. 38-41. 



Erichsonella filiformis Richardson, American Naturalist, XXX I \', 1900, p. 228; 

 Proc. r. S. Nat. Mus., XXIII, 1901, p. 543. 

 28589—05 26 



Fig. 447. — Erich- 

 sonella atten- 



lATA. MAXIL- 

 LIPED. X 20i. 



