0LIG0CH.5KTA. 275 



3. Beddard, F. E. — A Revision of the Earthworms of the Genus 



Amyntas {Perichseta). P. Zool. Soc, Lond., 

 1900. 



4. Bousfield , E. C. — The Natural History of the Genus Dero. J. Linn . 



Soc. (Zool.), XX., 1890. 



5. Michaelsen, W. — Oligochseta, in Das Tierreich. Berlin, 1900. 



6. Hamburgische Elb-XJntersuchung, IV., Oligo- 



chseten. Hamburg, 1903. 



7. Die Oligoehaten Deutsch Ost — Afrikas. Zeit. f . 



wiss. Zool. Bd. LXXXII., 1905. 

 8. On a New Megascolex from Ceylon. Spolia 



Zeylamca, Vol. VI., 1909. 

 9. The Oligochseta of India, Nepaul, Ceylon, 



Burma, and the Andaman Islands. Mem. 



Ind. Mus., Calcutta, Vol. I., No. 3, 1909. 

 10. Stephenson, J. — On some Aquatic Oligochseta in the Collection 



of the Indian Museum. Rec. Ind. Mus., 



Calcutta, Vol. VI., Pt. 4, 1911. 



1 1 . On Branchiura sowerbyi, Beddard, and on a new 



species of Limnodrilus with distinctive charac- 

 ters. Trans. Roy. Soc. , Edin. , Vol. XL VIII. . 

 1912. 



12. Contributions to the Fauna of Yunnan. Part 



VIII., Earthworms. Rec. Ind. Mus., Cal-' 

 cutta. Vol. Vn., Pt. 3, 1912. 



13. Willey, A. — Convergence in Evolution. London, 1911. 



Desckiption of Figures. 



Plate I. 



Fig. 1. — Dero zeylanica; transverse section through posterior end, 

 cvitting both intestine and dorsal diver tie vilum of branchial fossa, 

 the latter containing the first pair of gills ; X 155, Abbe's drawing 

 apparatus. 



Fig. 2. — The same ; transverse section at a more posterior level ; 

 intestine has opened into the branchial fossa, which is still closed 

 dorsaUy ; the first and second pairs of gills as ridges on the walls of 

 the fossa ; X 155, Abbe's drawing apparatus. 



Fig. 3. — The same, more posteriorly still ; the branchial fossa has 

 opened out dorsally ; the first pair of gills has disappeared ; the 

 second, third, and fourth pairs are seen; x 155, Abbe's drawing 

 apparatus. 



Br. /., branchial fossa; d. d., dorsal diverticulum of fossa ; g^-g*, 

 first to fourth pairs of gills ; int. , intestine ; marg. , margin of fossa ; 

 sp. c, nerve cord ; x., pear-shaped epithehal cells of gills. 



Fig. 4. — Dorsal needle-seta of Dero zeylanica. 



Fig. 5. — Setae of Aulophorus palustris ; a, dorsal needle ; b, ventral 

 seta of segments II. -IV. ; c, ventral seta of segments behind IV. (6 and 

 c more highly magnified than a). 



2 o 6(7)12 



