Boone, Crustacea, Cruise of "Alva," 1931 195 



dactyl of the fifth leg is not different from those of the preceding 

 ambulatories. 



This species, which is very close to Thor paschalis Heller in 

 general appearance, differs in the presence of a strong supra- 

 orbital spine, in the different rostral dentition, and in the shape, 

 length ratio of the scaphocerite and in having two lateral spines 

 proximally on the scaphocerite. It differs from Thor discosmatis 

 Kemp in having five joints in the carpus of the second pair of 

 legs ; in the shape of the scaphocerite and dentition of the proximal 

 lateral margin of the scaphocerite; also in the rostral dentition, 

 the present species having one epigastric and two rostral teeth 

 besides the apical tooth. The present species has six spines on 

 the distal margin of the telson, where discosmatis has eight spines. 

 It differs also from T. maldivensis Borradaile in the rostral den- 

 tition and length ratio. The writer is aware that the specific char- 

 acters are very delicate, yet the present specimen does not fall 

 within any of the three species recognized by Dr. Kemp in his 

 excellent monograph. 



None of nearly a hundred specimens of Thor paschalis Hell- 

 er, from various localities in Florida, the West Indies and Carib- 

 bean coast, examined by the present writer, had a supraorbital 

 spine, although much variation in the rostral dentition occurred. 



Genus: LATREUTES Stimpson 

 Latreutes mucronatus (Stimpson) 



Plate 53 



Type: The type was collected in Hong Kong and, if extant, 

 is probably in the Philadelphia Academy of Natural Sciences. 



Distribution: This species is rather widely distributed in 

 the Indo-Pacific, having been reported from the Red Sea, the 

 southeast coast of Arabia (Nobili) ; two localities in the Ramnad 

 District, southern India, Port Blair, Andamans (Kemp) ; Che- 

 mulpo, Korea, Sagami Bay, Japan, Gulf of Siam (Balss) ; Sagami 

 Bay (Doflein) ; Hong Kong (Stimpson) ; Java (Nobili) ; Muntok, 

 Dutch East Indies (Boone) ; Cape Jaubert, Australia (Balss). 



Material examined : Two specimens, Muntok, Banka Island, 

 Banka Straits, Dutch East Indies, November 5, 1931, bv the 

 "Alva." 



