750 MB. W. F. LANCHESTER ON CETTSTACEANS [June 19, 



the basal joint of the antenna, but leaving the orbit widely open at 

 this point. 



The postfrontal ridge is sinuous and not straight : and the extra- 

 orbital tooth is lobular and not pointed, though its anterior angle is 

 rather sharp. In this latter respect it agrees with a description by 

 von Martens of seven Borneo examples (torn. cit.). As it has the 

 same shape in all these individuals irrespective of size or sex, I do 

 not think it is a peculiarity of age, as he at first suggests, but rather 

 one of local race : the possibility of which von Martens admits a few 

 lines further on. 



In none of these specimens can I find any traces of the longi- 

 tudinal groove of the median crest of the palate. As with Heller's 

 examples of the species (t. c), the meri of all five legs bear a sub- 

 terminal spine on their anterior margins : in all other respects 

 they agree with M.-Edwards's description. In colour they are uni- 

 formly dark brown above, with a tendency to yellow below. 



These crabs form burrows with two mouths, one of which would 

 open on the bank of the lake, just above the level of the water, the 

 other opening at a distance of at least 10 feet over a stream which 

 carries off the surplus water of the lake : the burrow, between its 

 mouths, being straight and horizontal, more or less. 



Tozzetti gives a figure of the internal angle of the orbit, but I 

 cannot determine from it whether the upper tooth is well- or ill- 

 developed, and he makes no mention of it in the text. He also 

 describes the sub-apical teeth of the meropodites as being much less 

 acute than in the Thelphusse generally, and figures that on the 2nd 

 pair, showing it to be more of a rounded lobe than a tooth : in all 

 five legs in this variety they are, on the contrary, very acute indeed. 

 External maxillipedes, male abdomen, and hands of chelipedes, how- 

 ever, entirely agree with his description and figures. 



Dim. 6 52x38-5. 6 42x33. 6 37x28. £ 38x30-75. 

 $ 19-75x16. 



Length taken from base of rostrum to middle of posterior 

 border. 



XLIII. Genus Caecinoplax M.-Edw. 



70. Cabotnoplax subintegeb, nom. nov. (Plate XL VI. fig. 9.) 



Carcinoplax Integra, Miers, 'Alert' Crust, p. 543, pi. xlviii. fig. C 

 (1884). 



Carcinoplax integer, de Man, Mergui Crust, p. 93 (1888). 



Hob. I am uncertain as to whether this was obtained at Singa- 

 pore or Malacca, or at what depth it occurs. 



3 males, and 1 female with ova. 



I propose to alter Mr. Miers's specific name in view of the fact 

 that the antero-lateral margins are not entire but dentated. This 

 I find to be the case in all my specimens (3 d" and 1 $ ), and also 

 in two examples in the Museum from the Mergui collection. 

 There are 4 teeth, small but distinct : the first two are low, broad, 

 and truncate, the 2nd about as broad as the first ; the 3rd, about 



