igio.] S. Kemp : Notes on Decapoda. 177 



single large fold involving nearly one-third of the whole plate. 

 When this fold is opened out the structure presents the appearance 

 shown in fig. 3. 



Gennadas sordidus, sp. nov. 

 (Plate xiv, figs, i — 3.) 



St. 193.— North of the Laccadive Islands, 15° 11' N., 72° 28' 

 45" E., 931 fathoms. One male, about 20 mm. 



St. 194. — Off the Laccadive Islands, 13° 47' N., 72° 3' 45" E., 

 891 fathoms. One male, 24 mm. 



St. 198.— North-east of Ceylon, 8° 55' N., 81° 17' 30" E., 764 

 fathoms. One male, i8|^ mm. 



The rostral crest does not differ appreciably from that of the 

 preceding species. The antennary and infra- antennary angles are 

 acute, the former being bluntly rounded and the latter sharp ; the 

 branchiostegal spine is very small. The distance between the 

 cervical and post-cervical grooves, measured dorsall5^ is less than 

 one-fifth the distance from the post-cervical groove to the hinder 

 margin of the carapace. The mid-dorsal carina is inconspicuous 

 behind the latter groove. 



The second joint of the antennular peduncle is very short ; 

 measured dorsally, it is less than half the length of the ultimate 

 joint. The antennal scale is widest at the base; it is three times 

 as long as wide and the outer margin terminates in a very small 

 spine which does not extend as far forwards as the lamellar portion. 



The ultimate joint of the mandibular palp is shorter than the 

 greatest width of the basal joint. In the second maxilla (fig. 3) 

 the anterior lobe of the internal lacinia is short, not wider at the 

 apex than at the base, and is little, if at all, narrower than the 

 adjacent lobe of the external lacinia. In the latter lacinia the 

 anterior lobe is about one and a half times as broad as the poste- 

 rior. The endopod is furnished with three curved spines near the 

 narrow apex. 



The third joint of the endopod of the first maxillipede is about 

 one and a half times the length of the second and the basal joint 

 bears two or three stiff spines on the inner distal margin. 



In the first peraeopods the chela , which is about as long as the 

 carpus, is about two-thirds the length of the merus. The chela of 

 the second pair is two-thirds the length of the carpus and the 

 dact5ius is equal to, or a trifle shorter than, the palm. In the 

 third pair the carpus and merus are exactly the same length ; the 

 dact3dus is as long as the ])alm, the whole chela being about half 

 the length of the carpus. 



The median spines on the abdominal sterna are not prominent ; 

 the sixth somite alone is dorsally carinate. The apex of the telson 

 has much the same form as in G. alcocki. 



The petasma (figs, i, 2) is a rather complicated structure and is 

 of much the same type as that of G. parvus, to which G. sordidus 



