On new Oenera and Species of MlUipedeft. A'21 



Mormyrus psittacus. 



Depth of body 3^ times in total lengtli, lengtli of liead \\ 

 times. Snout very sliort, strongly curved, hardly as long as 

 diameter of eye, wliich is 4^ times in length of head; mouth 

 terminal, below the level of the eye, its width \ length of 

 head ; teeth moderately large, notclied, 3 in the upper jaw, 4 

 in the lower ; chin slightly swollen. Dorsal 33, originating 

 halfway between end of snout and caudal and considerably in 

 advance of anal ; longest rays '^ lengtli of head. Pectoral a 

 little shorter than head, reaching base of ventral ; latter ^ 

 length of head. Anal 23, originating below thirteenth dorsal 

 ray ; longest rays | length of head. Depth of caudal 

 peduncle ^ its length. Scales 60 ^ ; 12 scales round caudal 

 peduncle. Silvery, dark grej' on the back. 



Total length 125 millim. 



A single specimen. 



This species is probably the same as M. dlscorhjnchus, 

 Schilthuis (nee Peters). M. discorhynclius differs in the snout 

 projecting beyond the mouth, the smaller scales (05-70 j^), and 

 the deeper caudal peduncle (2-2^ as long as deep). 



LI. — New Genera and Sjjecies of Millipedes of the Family 

 Platyrrhachidse from the Indo- and Austro-Malayan Sub- 

 reyionSy contained in the Collection of the British Museum. 

 By K. I. PococK. 



Most of the material upon which this paper is based has 

 been acquired by the Trustees of the British Museum, during 

 the past ten years, from various collectors, like Messrs. G. Hose, 

 A. Everett, and H. N. Ridley, who are resident in the East 

 and have kindly forwarded the specimens to the Museum in 

 response to an appeal for examples of Millipedes. 



A few of the species here described as new may eventually 

 prove to be identical with species established by Peters in 

 1864. But without examination of the typos the identification 

 of Peters's species is almost impossible, owing to tlie absence 

 of figures and to the fact, recently established by Mr. Cook, 

 that in many cases the diagnoses were based upon two or more 

 recognizable forms *. 



* On behalf of collectors imfeniili.ar witli tbe taxonomy of the 

 Diplopoda, it may be explained that the Platyrrhachidae are for the most 

 part Millipedes of large or medium size, in which the body is composed 

 of twenty segments, each segment, except the lirst and the last, being 

 furnished on each side with a large more or less square and horizontal 

 plate which bears the pore. 



29* 



