207 



C. trtmcatifroHs has been discovered by the "Albatross" in a depth of 22 fathoms, in 

 Philippine waters. 



Dimensions in mm. : 



Fronto-orbital breadth .... 

 Width of front at anterior margin 

 Greatest breadth of carapace 



Length of carapace 



Posterior border of carapace . . 



2.75 



1.4 



5-5 

 3-4 

 4-3 



c^ 



85 



5 



3 



The last specimen bears a few eg 



gs, which are rather large (0.25 — 0.33 mm. in diameter). 



Typhiocarcinus Stimpson. 



1858. Typhiocarcinus Stimpson. Proc. Ac. Nat. Sc. Pliiladelphia, 1858, p. 95. 



This genus very much resembles Ceratoplax, but the eyes are so greatly reduced as to 

 be almost obliterated, and the pigment has completely disappeared, or nearly so; besides, the 

 antero-external angle of the merus of the external maxillipeds is not at all produced. Ouite 

 recently Miss Rathbun ^) described a new species of TypJdocarcinus, which in important facts 

 disagrees with the original understanding of the genus : the eyes are black and terminal, the merus 

 of the external maxillipeds is produced at the antero-external angle, the carapace well sculptured, 

 punctate, pubescent ; the transition between antero- and postero-lateral margins of the carapace 

 is marked by an obtuse tooth. Leaving this aberrant species aside there remain three species, 

 which are already discriminated by Alcock; I cannot, however, agree with him in separating 

 the species on account of the antero-lateral borders of the carapace being toothed or entire, 

 as this criterium is not always reliable. 



Key to the species : 



1. A faint pigment speek nearly in the middle of the subcircular eye-stalk. 2. 

 No pigment speek in the eye-stalk, the latter of a piriform shape. 



Inner angle of wrist of cheliped produced, dentiform. Animal of a 



ruddy-brown colour ■ T. rubidus Alcock -) 



2. Ratio of length of carapace to breadth i : 1.6. Lateral margins of 



buccal cavity divergent backward; exognath of external maxillipeds 

 narrow (one-fourth the breadth of ischium). Chelae almost smooth, 

 walking legs little hairy; dactyli of last pair curved upward and 



backward T. niidtis Stimpson 



Ratio of length of carapace to breadth i : 1.3. Lateral margins of 

 buccal cavity subparallel; exognath of external maxillipeds broader 

 (about one-third the breadth of ischium). Large chela of cf smooth, 

 smaller one pubescent; both chelae of 9 pubescent; walking legs 

 fringed with hairs; dactyli of last pair straight, not curved ... 7". villosus Stimpson. 



1) T. crattrifer Rathbun, Proc. U. S. Nat. Mus., v. 48, 1914, p. 147. Hab. Philippine waters, depth 80 fathoms. 



2) Journ. As. Soc. Bengal, v. 69, prt 2, 1900, p. 323. Hab. Bay of Bengal, depth 20 — 65 fathoms. 



59 



