ISOPODS OF NORTH AMERICA. 



375 



PENTIDOTEA STENOPS (Benedict). 



Idotea stenops BENEDICT, Proc. Biol. Soc. Washington, XII, 1898, pp. 54-55. 

 RICHARDSON, Proc. U. S. Nat. Mus., XXI, 1899, p. 846; Ann. Mag. Nat. 

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

 Harriman Alaska Exp. Crust., X, 1904, p. 219; Proc. U. S. Nat. Mus., 

 XXVII, 1904, p. 663. 



Locality. Monterey Bay, California. 



Body oblong-ovate, nearly three times as long as wide, 15 mm. : 42 mm. 

 Head nearly twice as wide as long, 4 mm.: 7 mm. Frontal margin 

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

 transversely elongated, being' five times as wide as long and are situ- 

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

 greatly dilated; the three following articles are short 

 and nearly subequal. The first pair of antennas 

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

 duncle of the second pair of antennae. The first arti- 

 cle of the second pair of antennas is short and does 

 net extend beyond the basal article of the first pair 

 of antennae; the second and third articles are sub- 

 equal; the fourth and fifth articles are also subequal 

 and each is a little longer than either of the two pre- 

 ceding articles. The fla- 

 gellum is composed of fif- 

 teen articles. The second 

 antennas extend to the 

 posterior margin of the 

 second thoracic segment. 

 The maxillipeds have a palp composed of 

 five articles. 



The first 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 are subequal. 

 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 occu-py almost the 

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

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

 below the epimeron. The last three epimera occup}' 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 segments 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- 



FIG. 407. PENTIDOTEA 

 STENOPS (AFTER 

 BENEDICT). 



FIG. 408. PENTIDOTEA STENOPS. 

 a, MAXILLIPED. x Hi. b, FIRST 



ANTENNA. X Hi- 



