62 THE VOYAGE OF H.M.S. CHALLENGER. 



Colour. — The alcoholic specimens have the carapace mottled with dark brown 

 pigment, with four sharply defined dark spots close to its posterior edge, six elongated 

 pigment spots on the third, six on the fourth, four on the fifth, and four on each of the 

 first five abdominal somites. Miers says that his specimens from the Samoan Islands were 

 dull olive green, with branchial appendages pink, but those colours are not preserved in 

 the specimens which I have seen. 



Habitat. — The Challenger collection includes two specimens, a male and a female, 

 from 8 fathoms at Station 186, near Cape York, lat. 10° 30' S., long. 142° 18' E. Miers 

 records it from Torres Straits and from other points in Northern Australia, as well as 

 from the Eed Sea, Ceylon, Gulf of Suez, Seychelles, Samoa Islands, Amboina, and other 

 localities in the Indo-Pacific region. 



Size. — Largest male specimen, 2^*^ inches from tip of rostrum to middle of 

 telson. 



Gonodactylus glabrous, n. sp. (PI. XIV. fig. 5 ; PI. XV. figs. 7, 9). 



Diagnosis. — Dactylus of raptorial claw wdthout teeth, and dilated at base. Eos- 

 trum with a long slender acute median spine, and subacute lateral angles. Hind 

 body wider than the carapace, Tvdth its sides straight and parallel. Second thoracic 

 somite slightly exposed dorsally. Lateral edges of aU the abdominal somites with 

 triangular marginal carinse with the apices directed backwards. Dorsal surfaces of the 

 thoracic and first five abdominal somites without carinse or spines. Sixth abdominal 

 somite without a median carina, and with three pairs of lateral carinse, aU ending in 

 spines, the submedian and intermediate being swollen and convex, while the marginal 

 is more narrow and linear. The second or intermediate is shorter than the first and 

 third. Telson ending in six acute spines with broad bases, and each with a sharply 

 defined narrow longitudinal dorsal carina. Middle of dorsal surface of telson with, a pro- 

 tuberant hemispherical eminence, upon which are five narrow sharply defined carinse, of 

 which the median and the two submedian end posteriorly in spines, while the marginal ones 

 are without spines and shorter than the others. There is a triangular subacute promin- 

 ence on the anterior edge of the dorsal surface of the telson on each side, halfway between 

 the middle line and the lateral margin, with a narrow sharply defined carina. Paddles 

 of exopodites of uropods less than half as long as the second joint. The basal joint of 

 the uropod has only one acute spine on its dorsal surface, while its ventral prolongation 

 ends in two nearly equal spines, with an obsolete rounded tooth on the inner margin of 

 the outer one near its base. The tergal surfaces of the abdominal somites have no trans- 

 verse or longitudinal sutures. 



General Description. — This species is so very similar to Gonodactylus graphurus in 

 every prominent characteristic that the description of that species will serve for this also. 



