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Dimensions in mm. ^) : 



Distance between external orbital angles 6.9 



Width between posterior epibranchial teeth lO.i 



Width of front between eye-stalks 2-4 



Length of carapace 8.0 



Length of posterior margin of carapace 5.1 



Length of cheliped 10.25 



Horizontal length of chela 4.75 



Length of palm 3-o 



Height of palm 2.15 



Breadth of abdomen at base 3.1 



Breadth of posterior margin / r , , I i.S 



of penultimate segment of abdomen I 

 Length \ ( i-i 



Breadth of posterior margin i r 1 1 i '-5 



of terminal segment of abdomen ( 

 Length \ ( i-3 



Length of 2<i pair of walking legs 15.3 



Length ) . . i 6.1 



! of meropodite of 2d pair 

 Breadth \ ^ ' ( 1.8 



Length of carpo- and propodite i \ 6.3 



I of 2^1 pair I 

 Length of dactylus ) ( 2.0 



The largest specimen measured by Stimpsox (a 9) '^\'as of about tlie size of tlie animal 

 now described. 



Tylodiplax de Man. 

 1895. Tylcdiplax de Man. Zool. Jahrb., Syst., Bd 8, p. 598. 



The lateral margins of the carapace are strongly divergent backward and unarmed, the 

 chelipeds, even in the cf, exceedingly small and weak, and the ma.xillipeds, the exognath of 

 which is wholly exposed, are auriculate at the antero-external angle of the merus -). 



Two species are contained in the genus, but the systematic place of one of these is doubtful. 

 Key to the species : 

 Front obliquely-deflexed. Carapace with two prominent tubercles 

 on the cardiac region, and two less prominent ones at the anterior 

 angles of the intestinal region. Chelipeds of cf excessively small 



and weak T. tctratylopJwrits de Man **) 



Front not deflexed. Carapace somewhat hairy at the margins, but 

 without the prominent tubercles. Chelipeds of cT somewhat larger, 

 but shorter than most of the walking legs ....... T. indica Alcock *) 



1) Measured under microscope. 



2) De Man states that this genus is distinguished from CUislostoma by having the merus of the external maxilliped larger 

 (longer) than the ischium, but this character is observed quite as well in the latter genus. 



3) Zool. Jahrb., Syst., Bd 8, 1S95, p. 599, pi. 14, f. 15. Hab. Penang. 



4) L. c.'p. 374. 111. Zool. "Investigator", Crust, prt 10, pi. 64, f. 2. Alcock doubts whether Tylodiplax should not be united 

 with Paracleistosloma or Clcistostoma. The development of the chelipeds in the immature ^ (found at Karachi) renders it uncertain 

 whether in the adidt form the cheliped should not attain the normal size of that the other named genera, but I am of opinion, that even 

 then the shape of the exleroal maxillipeds would justify the maintenance of Tylodiplax. 



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