86 AN EXPEDITION TO MOUNT KINA BALU. 



The dactyles of the walking-legs are rather shorter and 

 stouter than is indicated in de Man's figure of the allied P. 

 metadata, The fingers of the chelee are dark in colour. P. 

 convexa is already recorded from Java, Timor, and New Guinea, 

 and doubtfully from Borneo 1 . P. maculata (de Man) 1879 is 

 a closely allied form from Sumatra. 



1 $ British North Borneo." 



3. "Potamon (Thelphusa) 2 consobkinum, deMan. 

 Potamon (Potamori) consobrinum, de Man, Notes Leyd. Mus. 



xxi. p. 99, pis. vi., ix., x. fig. 10 (1899). 



This species is already reported from Borneo (Mt. Damoes 

 and Upper Sibau River) by de Man. Ortmann (Zool. Jahrb. x. 

 Syst. p. 301) gives a list of allied forms and their distribution. 



2 J, 1 ? ; Kadamaian River, Kina Balu, 2,100 feet." 



4. " POTAMON (GEOTHELPHUSA) KADAMAIANUM, n. sp. 



A single female specimen of a form allied to P. obtusipes 

 (Stimps.) 1858, and P. dehaani (Gray) 1847, seems to deserve a 

 name of its own. Whether it were not better treated as a local 

 race of one of the above species, or all three as local forms of 

 P. dehaani, is a question to be settled when the subject of the 

 interrelationship of the various forms in the genus comes up for 

 discussion. In the meantime its distinctness seems quite as great 

 as that of several of the generally accepted species. It differs 

 from P. obtusipes in the greater slenderness of its legs, especially 

 of the dactyles, which are long and narrow and end in a sharp 

 claw.* A Potamon of the subgenus Geothelphusa with the surface 

 of the carapace smooth and finely pitted over the greater part of 

 its extent, finely granular on the front, more coarsely so on the 

 forepart of the branchial region, rugose on the hinder part of the 

 same region ; the front much deflexed, ending below the outer 

 angles of the orbits, when viewed in front bounded by an almost 

 straight line curving away gradually towards the outer angles ; 



iMiers, Ann. Mag. Nat. (5) v. p. 306 (1880). 



2 According to Ortraan (Zool. Jahrb. x. Syst. 300) Thelphusa is .the 

 correct name, for the subgenus in which this species must be placed. 



* The portion defined by asterisks was by Mr. Borradaile's wish sub- 

 stituted for the original passage in the P. Z. S. 



