CEUSTACEA ISOPODA OF THE 'POECUPINE' EXPEDITION. 237 



Tribe ASELLOTA. 



1882. Asellota G. O. Sars, Forh. Selsk. Christian, no. 18, p. 16. 



1897. Asellota G. O. Sars, Crustacea of Norway, vol. ii. part v. p. 94. 



1905. Asellota H. J. Hansen, Proc. Zool. Soc. London for 1904^ p. 302. 



1905. Aselloidea or Asellota Harriet Richardson, Bull. U.S. Nat. Mus. no. liv. p. 408. 



1910. Asellota Stebbing, Trans. Linn. Soc. vol. xiv. part i. p. 108. 



1910. Asellota Stebbing, S.A. Crust, in Ann. S. African Mus. vol. vi. part iv. p. 435. 



Fam. ThAM BEMATID^. 

 Stebbing,|Abstract P. Z. S. 1912, p. 42 (Nov. 5th). 

 As the new genus for which this family is named stands alone, its characters, if 

 rightly made out, will for the present be those of the family. 



Gen. Thambema, 



Stebbing, Abstract P. Z. S. 1913, p. 42 (Nov. 5th). 



Body narrowly elongate, with all seven segments of perseon distinct and all seg- 

 ments of the pleon consolidated; flagellum of first antenna short, few-jointed; 

 mouth-organs in general agreement with those of the tribe Asellota ; first gnathopods 

 stouter than the three following pairs of limbs, but all similar in pattern, not chelate 

 or subchelate ; pleopods not exceeding four pairs ; uropods entirely wanting. 



The genus is founded on specimens exclusively of the male sex and in which the 

 second antennge are seemingly imperfect, and the last three pairs of peraeopods have 

 undoubtedly lost all the structure following the second or basal joint. 



The generic name is derived from the Greek word 6af^i(3>jfxa, a marvel, in allusion to 

 the peculiar characters of the pleon. It may be assumed that the missing pleopods 

 are the fifth, a pair which is already reduced to single plates in Janiridse and Desmo- 

 somatidte. The want of uropods occurs, so far as known, nowhere else in this tribe, 

 their absence from Stenetruim serratum, Hansen being in all probability accidental. 



Thambema amicoeum. (PI. XXVI. j 

 Stebbing, Abstract P. Z. S. 1912, p. 42 (Nov. 5th). 



The body is, on the whole, parallel-sided, but with a slight distal narrowing of the 

 perseon segments. The head is produced between the antennae into a broadly rounded 

 lobe, in advance of which appear the terminal joints of the two mandibular palps. 

 The antero-Iateral corners are slightly produced, but not occupied by any discernible 

 organs of vision. The pleon is broadly oval. 



The first antennae lie just over the second, with a first joint broader but not longer 

 than the next, which is broader than and nearly twice as long as the third ; to this 

 peduncle succeeds a flagellum of one rather long joint between two short ones, with 



