1914-] S. Kemp : Notes oh Crustacea Decapoda. 121 



Genus Merguia, nov. 



Carapace without supra-orbital or antero-Iateral (pterygosto- 

 mian) spines ; antennal spine present. Upper antennular flagellum 

 uniramous. Mandible without incisor-process or palp. Third 

 maxillipede without exopod. Neither epipods nor arthrobranchs 

 at base of first four peraeopods. Carpus of second peraeopods 

 composed of many (24 or 25) segments. 



This genus is founded to receive de Man's Hippolyte oligodon, 

 of which species the type and only known example is preserved in 

 the Indian Museum. 



Examination of the mandible shows that both incisor-process 

 and palp are absent (pi. VII, fig. 8) and that in the number of 

 segments in the carpus of the second peraeopods and in the sup- 

 pression of the arthrobranchs at the base of the first four thoracic 

 limbs it approaches the genera Lysniata and Hippolysiiiata. From 

 both these it is easily distinguished by the absence of the exopod 

 on the third maxillipede and of the epipods at the base of the 

 peraeopods. 



In addition the species differs from other Hippolytidae in 

 two very peculiar features. The first of these is the enormous 

 development of the second segment of the antennal peduncle, which 

 reaches beyond the apex of the antennal scale : this feature is well 

 shown in de Man's figure The second is the undivided condition 

 of the distal endite of the second maxilla (pi. VII, fig. 9). Except 

 in the Pasiphaeidae in which both endites are suppressed, the 

 distal endite is. in the Caridea. alwavs divided. 



Merguia oligodon (deMan). 

 Plate VII, figs. 8,9. 



1S8S. Hihpolyte oligodon, de Man, journ. I, inn. Soc, XXII, p. 27, pi. 

 xviii, figs. I -6. 



To de Man's detailed description there is little to add except 

 as regards the characters of the oral appendages, noted above, 

 the absence of the exopod on the third maxillipede and the 

 suppression of the epipods at the base of the peraeopods. 



The specimen, as de Man noted, is not in perfect condition ; 

 the antennules are broken off shortly above the base of the 

 peduncle, but enough remains to render it almost certain that no 

 additional ramus is present on the upper flagellum The flagellum 

 is, indeed, very different in appearance to that found in Hippoly- 

 sniata^ for it is round in section and without setae, whereas in 

 the preceding genus it is more or less oval at the base, apparently 

 formed by the fusion of two rami, and bears numerous setae, 

 probably olfactory in function, on its inferior aspect. 



«-2_3o Klphinstone I., Mergui Archipelago. |. .Xnderson. One, 28 mm. 



TYPE. 



