332 A HISTORY OF RECENT CRUSTACEA 



telson. The animal, especially the male, is vermiform. 

 The mouth-organs have not been described. Mr. Haswell 

 speaks of the outer branch of the uropods as ' an appen- 

 dage which is directly articulated with the posterior border 

 of the segment,' a very strange peculiarity. 



Haliophasma, Haswell, 1880, would seem to be a 

 synonym of AntJmra, since the species Ilaliopliasma macu- 

 lata, Haswell, has been described by Ohilton under the name 

 Anthura affinis, and stated by him to be a true Anthura. 



Ptilanthura, Harger, 1878, is probably also a synonym 

 of Anthura, the one-jointed mandibular 'palp' being due, 

 it may be supposed, to a defect of the specimen observed. 



The nest two genera agree in having the lower lip 

 bipartite but acuminate ; the mandibles without teeth, 

 lancet-like, lobes at the base forming a channel for the 

 liquid drawn by the thrust of the lancets ; the first maxilla? 

 spear-like, distally channelled and serrate ; the maxillipeds 

 elongate, consisting of four or five joints, the second of 

 which is elongate. 



Paranthura, Bate and Westwood, 1866. The flagellum 

 of the first antennas in the male forms a large multi- 

 articulate brush, in the second it is rudimentary. The 

 mandibular 'palp' is three-jointed. The pleon has six 

 segments and the telson distinct. The outer branch of 

 the uropods is short, variable in width. 



Calathura, Norman and Stebbing, 1886. The antennas 

 of both pairs in both sexes have many-jointed flagella, 

 that of the first pair perhaps not greatly developed in the 

 male. The pleon has six segments and the telson dis- 

 tinct. The outer branch of the uropods is short and wide, 

 overarching. 



Oruregens, Chilton, 1882. Both pairs of antennas are 

 short, few-jointed. The second pair have a small exopod. 

 There is no mandibular ' palp,' but otherwise the mouth- 

 organs bear a general resemblance to those of the two 

 preceding genera. The seventh segment of the peraeon is 

 very short and devoid of limbs. The pleon has six seg- 

 ments and the telson distinct. The outer branch of the 

 uropods is narrow, not overarching the squamiforrn telson. 



