230 J. Wood-Mason — On Hew or Utile-Fcnown Crustaceans. [Dkc. 



however, exhibited some excellent photographs of the animal in question, 

 and of R. Indicus, and pointed out the differences in the structure of the 

 epidermal exoskeleton in the two species. 



Mr. Wood-Mason exhibited the materials for his monograph of Paratel- 

 phusa, an Indo-Malayan genus of freshwater crabs, of which he recognized 

 altogether seven perfectly distinct and well-marked species ; of these five had 

 been or are now described by himself. The genus, he said, was established 

 in 1855 by M. Milne- JM wards for the reception of two new species of 

 crabs, one of which was supposed to have come from the China Seas, the 

 other from New Zealand ; but the localities given had proved to be incorrect, 

 the former being really a native of the freshwaters of Southern China and Siam, 

 the latter of those of the three great Sunda Islands — Java, Sumatra, and 

 Borneo. Mr. Wood-Mason, in 1871, himself described two additional spe- 

 cies, the one from upper Burmah, the other from India, wherein it ranged 

 from Hardwar, the point at which the Ganges issues from the Siwalik Hills, 

 throughout the Gangetic valley down to Calcutta, where brackish water 

 conditions obtained, and where it occurred both in fresh and brackish water 

 like several of its congeners. It was an interesting fact that all the species 

 described by him inhabited countries the fauna of which was largely 

 leavened, to say the least, with Malay forms, if indeed such forms did not 

 predominate. We were indebted to Mr. W. T. Blanford, than whom nobody 

 had ever done more for the distribution of animals in India, for dividing up the 

 vast tract of country commonly called India into a number of zoological 

 sub-provinces, to one of which, viz., to that denominated by him the Eastern 

 Bengal Province, with the Burmese countries and Assam added, the Paratel- 

 •phusas were confined: Calcutta, Mr. Blanford had said, was on the edge of 

 this province and rather in than outside of it ; and Calcutta accordingly had 

 its species of the genus in its common tank-crab. If we turned from these 

 invertebrates to seek an instance amongst the higher animals of this Ma- 

 layan leaven in the fauna, no more conspicuous one could possibly be found 

 than the interesting animal represented in one of the beautiful photographs 

 exhibited, — the Mliinoceros Sondaicus, which inhabited not only the Sun. 

 derbans near Calcutta but the great island of Java also. In conclusion 

 Mr. Wood-Mason said that he could not but look forward with much 

 interest to see whether species of Paratelphusa would be found in Ceylon 

 and in Malabar, the fauna of which curiously enough was also Malayan. 



The following are the new species : 



Paratelphusa Martensi. 



Latero-anterior margins of carapace armed with three epibranchial 

 teeth, the first tooth flattened, similar to the extraorbital angle but smaller, 

 the rest salient, acute, and conical. Post-abdomen of the male triangular — 

 as in P. Dayana, W-M. 



Hob. — Throughout the Gangetic valley, from Hardwar to Jessor, 



