times, in younger ones tvvice as long as the palm, slender, 



tapering, gaping, their inner margins fringed vvith hairs. . brevicristatus de Haan l ) 



(W. DE HAAN, Fauna Japon. Crust. 1849, p. 177 (A. malabaricus), PI. XLV, fig. 1, 

 vide also J. G. de Max, 1. c. 1909, p. 152, 158). 



e„ Fingers of larger chela very short, hardly more than half as 

 long as the palm, when measured horizontally, dactylus 

 stroncrly curved. Finkers of smaller chela of the male almost 

 twice as long as the palm, arcuate, gaping, not excavate 

 internally, their margins fringed with long stiff hairs. . . barbatus Cout. 

 b, Fingers of smaller chela of the male at most one-third longer than 

 the palm, dactylus "Balaeniceps"-shaped. 

 c l Merus of 3" 1 legs unarmed. 



d x Merus of 3 rd legs 5-times as long as wide. 



c\ Rostral carina not continued backward beyond the base of 



the orbital hoods, but the gastric region marked in the 



middle with a narrow, quite smooth band, on either side of 



which the surface is coarsely punctate. 



f l Larger chela of the male 3-times, smaller chela 3,6-times 



as long as high, with a transverse groove near the base 



of the dactylus. Terminal spine of scaphocerite hardly 



reaching beyond the scale djeddensis Cout. 



(H. COUTIÈRE, in: Notes from the Leyden Museum, XIX, 1898, p. 202 Vide also 

 J. G. de Man, I. c. 1909, p. 160, Pi. VIII, Fig. 25, 26). 



f„ Larger chela 2, 5-times, smaller chela of the male 3-times 

 as long as high, the latter with no transverse groove. 

 Terminal spine of scaphocerite extending by one-fourth 



of its length beyond the narrow tip of the scale . . . djiboutensis de Man 

 (J. G. de Man, 1. c. 1909, p. 160, PI. VIII, fig. 17 — 24), 



t'., Rostral carina continued to the middle of the carapace, obtuse 

 in the male, a little sharper in the female. Larger chela 

 2,4-times, smaller chela of the male 3,45-times as long as 

 high, the latter with a transverse groove near the dactylus 

 and with the fingers slightly longer than the palm. Carapace 



pubescent pubescens de Man 



d„ Merus of 3 ld legs 4-times as long as wide. Rostral carina 

 almost inconspicuous posterior to the orbital hoods. Larger 

 chela of the male 2,5 5-times, smaller chela 3-times as long 



1) Alphais kingsleyi Miers, in Proc. Zool. Soc. London, 1879, p. 54, ought probably to be considered as a young specimen of 

 A. trevicristaius. An examination of the typical specimen in the British Museum showed the following. The rostral carina is not continued 

 backward beyond the orbital hoods: the telson, grooved longitudinally, much resembles that of A. distinguendus. Larger chela with the lower 

 margin of the palm narrow, that of the fingers rather sharp; merus, like that of the other cheliped, with the upper margin unarmed at apex. 

 In the left leg of 2 nd pair the i st cavpal article proved to be one and a half as long as the 2" d , in the right leg hardly longer than 2 1 " 1 . 



191 



