BRACHYSCELIDAE 293 



Brachyscelus globiceps (Claus). 



Claus, 1887, p. 59, pi. xvi, figs. 1, 2, 4-10. 

 Stephensen, 1925 a, p. 176, fig. 65. 

 ? Stebbing, 1888, p. 1555, pi. cxcvii, fig. C (latipes). 

 Occurrence: St. 273. Portuguese West Africa. 1 ? 13 mm. (breadth of head 4-5 mm., of peraeon 

 5 mm.). 



Remarks. As regards the telson and uropods this specimen agrees better with 

 Stebbing's figure than with Stephensen 's, the telson being apically rounded, and the 

 outer ramus of uropod 3 four-fifths the length of the inner ramus. 



The conspicuous scale markings mentioned by Stebbing are not visible, but the 

 integument of the peraeon and pleon is minutely scabrous. 



I am not quite satisfied that this specimen is correctly identified with Claus' species. 

 Neither Stebbing nor Stephensen make any special mention of the breadth of the head 

 and peraeon, which is particularly noticeable in comparison with crusculum. In fact at 

 a first glance it appears to be a Thomneus, but the 4th-6th joints of peraeopod 4 are 

 regularly pectinate on their margins, and are without the additional setae found in 

 T. platyrhynchns . 



Distribution. Mediterranean; Zanzibar; South Pacific (latipes). 



Genus Thamneus, Bov. 

 Stebbing, 1888, p. 1558. 

 Stephensen, 1925 a, p. 180 (Euthamneus). 

 Pirlot, 1929, pp. 152, 153 (Euthamneus). 



I cannot follow Pirlot in separating Thamneus and Brachyscelus into different families. 

 They appear to me to be intimately related, and Stebbing (1888, p. 1555) considered 

 B. bovallii as in some respects a connecting link between the two genera. With a series 

 of forms like bovallii, globiceps, rapacoides, the difficulty is to find a distinctive character 

 separating the two genera. At first sight it appears that the very regular pectination of 

 the margins of the 4th-6th joints of peraeopod 4 is absent in Thamneus (it is not shown 

 in Stephensen's fig. 70, and only indistinctly in Stebbing's figure, pi. cxcviii), but it is 

 present in the specimen here examined, though nearly obsolete on the 4th joint. 



The articulation of the telson with the last pleon segment is not a distinguishing 

 feature, as the telson is just as movably articulated in Brachyscelus as in Thamneus. 



Under the International Nomenclatorial Rules the original name must stand. 



Thamneus platyrhynchus, Stebb. 



Stebbing, 1888, p. 1558, pi. cxcviii. 



Stephensen, 1925 a, p. 180, figs. 69, 70 (Euthamneus p.). 



Spandl, 1927, p. 210 (Euthamneus p.). 



Occurrence: St. 281. East mid-Atlantic. 1 $ 7-5 mm. 



Remarks. Though the types of rostra t us are no longer extant, Stephensen thinks that 

 in all probability this species is the same as Bovallius' species. 



Distribution. Mediterranean; Atlantic, about 5i°N-5° S; Indo-Pacific; Cape of 

 Good Hope (rostratus). 



