1909.] FROM THE BAY OF BISCAY. 869 



Third iiropods (fig. 45).— The peduncle as long as the telson ; 

 rami broad, subeqnal in length to the peduncle, the outer ramus 

 a little, the shorter; margins bordered with sensoiy spinules. 

 The peduncle has three I'ows of these spinules. 



Distribution. Taken by the 'Caudan' Expedition, 1895, 44° 

 17' ]Sr., 4" 38' W., in 940 metres; bottom deposit, mud. 



By the ' Huxley,' August 26, 1906, at Station XTI., 48° 7|' N., 

 8° 13' W., about 240 miles to the N. W. of the ' Caudan ' station, 

 in 246 fathoms ; bottom deposit, fine sand. 



Genus Rhachotropis S. I. Smith, 1883. 

 For synonymy see Stebbing (40), pp. 347, 729. 



Rhachotropis rcstrata Bonnier, 1896. (Plate LXXXI. 



figs. 46-48.) 



Rachotropis rostrata Bonnier (4), p. 653. 



4 specimens, all males, measuring respectively: 10, 10, 9*5, 

 and 9 mm. 



I have only one or two points to add to the excellent descrip- 

 tion and figures given by Bonnier. On p. 655, he states : " la 

 mandibule a un apex sans denticulations, avec un processus 

 accessoire denticule, bien developpe sur I'un des appendices et 

 rudimentaire sur I'autre." In these specimens, however, as will 

 be seen by the figures (47, 48) the ctittivg-plate is elongate, 

 incurved, with a strong tooth above, regularly crenulate in the 

 right mandible, the lower end of which is bidentate, and having 

 several irregular crenulations on the left mandible with the lower 

 end rounded and deeply incurved. Both accessory plates are well 

 developed ; the margin of the left divided into 8 teeth ; the 

 right, as in E. hiscayensis, of a more complicated construction, 

 forming distally 2 strong broad teeth, with 13 serrations above, 

 and having the upper part of the plate divided and its inner 

 portion produced to a long falciform tooth (cf. R. helleri, fig. 54). 

 The left spine-row has 3 spines, the right 2, each with a plumose 

 brush-like bristle behind. 



BistribHtion. Taken by the 'Caudan,' 1895, 44° 17' K, 4° 

 38' W., in 950 metres ; bottom deposit, mud. 3 specimens male. 



By the ' Huxley,' August 26, 1906, at Station XII., 48° 7^' N., 

 8° 13' W., in 246 fathoms; bottom deposit, fine sand. 



Rhachotropis helleri Boeck. (Plate LXXXI. figs. 49-65.) 



For synonymy see Stebbing (40), p. 351. 



20 specimens: 1 male measuring 8'75 mm.; 19 females from 

 10-12-5 mm. in leugth, one specimen with a young one 2-25 mm. 

 long still remaining in the incubatory pouch. 



These specimens showed several points of diflerence from the 

 R. helleri figured by Sars (29), pi. 150, viz., all the segments of 

 the person dorsally raised, the 7th pergonal segment with 

 lateral carina?, and the first three pleon-segments with the 



59* 



