ISOPODS OF NORTH AMERICA. 



375 



PENTIDOTEA STENOPS (Benedict). 



Idotea denops Benedict, Proc. Biol. Soc. Washington, XIT, 1898, pp. 54-55. — 

 Richardson, Proc. U. 8. Nat. Mas., XXI, 1899, p. 846; Ann. Mag. Nat. 

 Hist. (7), IV, 1899, p. 266; American Naturalist, XXXIV, 1900, p. 227; 

 Harriinaii Alaska Exp. Crust., X, 1904, j). 219; Proc. U. S. Nat. Mus., 

 XXVII, 1904, p. 663. 



Locality. — ^Monterey Bay, California. 



Bod}' oblong-ovate, nearly three times ay lono- as wide, 15 mm. : 42 mm. 

 Head nearly twice as wide as long, -t mm. : 7 mm. Frontal margin 

 slightly excavate between the antero-lateral angles. The eyes are 

 transversely elongated, l)eing live times as wide as long and are situ- 

 ated at the sides of the head. The basal article of the tirst antennae is 

 greatly dilated; the three following articles are short 

 and nearly subequal. The first pair of antenna? 

 extend to the end of the second article of the pe- 

 duncle of the second pair of antennte. The tirst arti- 

 cle of the second pair of antennte is short and does 

 n©t extend beyond the l)asal article of the tirst pair 

 of antenna>; the second and third articles are sul)- 

 ecpuil; the fourth and fifth articles are also subequal 

 and each is a little longer than either of the t\\'o pre- 

 ceding articles. The fla- 

 gellum is composed of fif- 

 teen articles. The second 

 antenntB extend to the 

 posterior margin of the 

 second thoracic segment. 

 The maxillipeds have a palp compo.sed of 

 five articles. 



The tirst segment of the thorax has the 

 lateral parts expanded and produced anteri- 

 orly, surrounding the posterior half of the 

 head. The second, third, and fourth seg- 

 ments are subequal and longer than the first, 

 fifth, and sixth segments, which aresube(iual. 

 The seventh segment is a little shorter than 

 the sixth. The epimera are distinctly separated on all the segments 

 with the exception of the first. The first three occupy almost the 

 entire lateral margin, the epimera being 5 nun. long, and the post- 

 lateral angle of the segment occupying ^ mm. of the lateral margin 

 below the epimeron. The last three epimera occupy the whole of the 

 lateral margin; they are very broad, the last two being broader pos- 

 teriorly than anteriorly. 



The abdomen is composed of three segiuents — two short ones, fol- 

 lowed by a long terminal segment which has at its base a suture line 

 on either side, indicating another partly coalesced segment. The ter- 



FlR. 407.— PENTIDOTEA 



STENOPS (After 

 Benedict). 



Fl(i. 108.— PENTIDOTEA STENOPS. 



a, Maxilliped. x II5. h, First 



ANTENNA. X lli. 



