PBOM SIAM AND MALAYSIA. 



325 



Anal tergite lightly constricted ; caudal process puuctulate, 

 moderately robust, the apex slightly upturned ; the valves large 

 and prominent, their margins evenly convex and strongly sulcate 

 from top to bottom ; the sternite defined by a groove. 



Gopulalory feet with the anterior lamina narrowed above, di- 

 lated and internally notched below, v^^ith its inner angle adorned 

 with an inwardly directed spur ; the protrusible portion armed 

 with a single stout spur at the base of the terminal membranous 

 expansion. 



Fig. 4. Spirosirept'us Hosei, sp. n. Anterior and j^osterior ends of body, and 



front view of left half of copulatory organ. 

 Fig. 5. Spiro&tre'ptvs Everettii, sp. n. Ditto. 

 Fig. 6. Spirostreptus haluensis, sp. n. Ditto. 

 Fig. 7. Spirostreptus dulitianus, sp. n. Ditto. 



Number of somites G5. 



Length about 150 millim. 



HaJ). A single male example from N.W. Borneo {R. Everett). 



Somewhat resembling the preceding {S. Hosei) in the shape of 

 the first tergite, but differing in the form of the copulatory feet, 

 of the anal valves, &c. 



SpIROSTEEPTUS DULTTTAlSrS, Sp. U. 



S • Colour black, caudal process and anal valves ferruginous, 

 the latter mesially infuscale ; antenna? and legs llavuus. 



