852 MRS. E. W. SEXTOX ON AMPHIPODA [Xov. 23, 



" molar expansion well-developed and of cylindi'ical form, 

 exhibiting the usual fluted ti'iturating surface" (29) p. 357. 

 The two species are, however, absolutely distinct, as will be seen 

 on comparison of the detailed figures of P. gracilis given below 

 with Sars's figures of P. glaber in vol. i. of the ' Crustacea of 

 Norway', pi. 126. fig. 1, gracilis having the typical molar of the 

 Para7)iphithoe degraded and almost rudimentary, while that of 

 glaber is well-developed and cylindrical. 



Stebbing (40) has retained the generic name of Parampliiihoe 

 Bruz., for Acanthosoma hystrix Owen and allied species, substi- 

 tuting the new generic name of Neoj^leustes for Paramphithoe 

 pidchella Kroyer and its allies. The type species of Parcvpleustes 

 Buch. being now proved to be a true Paramphithoe in the sense 

 in which Sars uses the name, and the genus Parapleicstes thus 

 becoming a synonym of Paramphithoe, the generic name 

 Parapleustes must take precedence ov^er JVeopleustes Stebbing, 

 and this latter name must therefore be cancelled. 



The species glaber Boeck falls into line wi|:h the Amphithce 

 latipes M. Sars, and for these, with Amphithopsis pulchella G. O. 

 Sars, A. olrikii Hansen, and A. grandimana Onevreux, Stebbing 

 (39) proposed in 1899 the generic name of Sympleustes. 



Parapleustes gracilis Buchholz, 1874. (Plate LXXX. figs. 1-7.) 



Syn. 1874. Parapleustes gracilis Buchholz (8), pp. 269, 299, tfe 



398, Taf. vii. fig. 1. 

 1882. Paramphithoe brevicomis Sai-s (27), p. 98, Taf. iv. 



fig. 11. 

 1887. „ gracilis Hansen (17), p. 124. 



1893. „ brevicornis Sars (29), pp. 353, 359, pi. 



124. fig. 2. 

 1906. Neopleustes brevicornis Stebbing (40), p. 313, and 

 Parapleitstes gracilis p. 320. 



The specimen described below is an adult ovigerous female, 

 measuring 6-75 mm. ; the specimen of Paramphithoe brevicornis 

 Sars, with which I have been able to compare it, is also an 

 ovigerous female but smaller, measuring only 3"75 mm. Sars gives 

 the average length of the adult female as " scarcely attaining 

 4 mm.," but he appears to have had only young specimens to 

 examine, which, while sexually mature, were not full-grown. 



Hansen (17), p. 124, says that the single specimen he ex- 

 amined agreed with both Buchholz's and Sars's descriptions and 

 figures, excepting in one or two trifling details : viz., the superior 

 antennse were rather longer than these authors stated, and the 

 2nd joint of the peduncle was very little shorter than the 1st, 

 agreeing with Buchholz's figure, Sars on the other hand showing 

 it as considerably shorter than the first joint. The same 

 diflference occurs in the two specimens I have examined, and 

 the proportions of the joints of the first gnathopod also differ 

 somewhat, but apai't from these small details, due entirely to age 



