341 



38. Siphoniulus albus sp. n. PI. XIX, fig. 13 — 13a. 



Sumatra: Manindjau. A single immature 9 specimen. 



Colour (in alcohol, of young) entirely white. 



Head longer than the rostrum; rostrum broad at the base pointed 

 apically. Antennae much longer than rostrum. 



Segments smooth, not hairy, the 1 st smaller than the 2»^, with 

 rounded inferior border. The rest finely striate longitudinally, and 

 furnished with a transverse sulcus. Pores conspicuous, situated about 

 halfway up the side of the segments. Anal segment annular, without 

 a caudal process. 



Number of segments 51. 



Length about 11 mm. 



Sub-order chordettmoidea , Cook and Collins '). 



Family CHORDEUMIDAE. 



Sub-family Heterochordeuminae nov. 



I propose this new sub-family for the reception of the peculiar genus 

 Heterochordeuma which differs from all the known European genera 

 and so far as I am aware from all those that have been described 

 from N. -America — which may be collectively referred to the sub- 

 family Chordeuminae — in possessing 32 body segments, each of which, 

 excepting the first and last, is provided with a wide depressed keel which 

 bears only one setiferous tubercle, the remaining two being situated 

 close together near the summit of the dorsum. In one European genus, 

 Atractosoma, which is also a strongly keeled form, two of the seti- 

 ferous tubercles are situated upon the keels. This difference, however, 

 is perhaps not more than of generic value. 



Heterochordeuma , Pocock. 



Ann. Mus. Genov. (2), XIII, p. 387. 



Head prominent vertex high, labral region strongly receding, labral 

 emargination tridentate; a cluster of ocelli on each side. Antennae 

 widely separated, elongate, the third segment the longest. Basal 



1) During a recent visit to the British Museum, Messrs. Cook and Collins, who 

 are doing some admirable work upon the Diplopoda, informed me that they propose 

 to elevate the Millipedes of the Chordeumid group to the rank of a sub-order equi- 

 valent to my Polydesmoidea. I entirely agree with the proposition. 



