DESCRIPTIONS OF GENERA AND SPECIES 475 



This species has been described by Bouene ; it chiefly differs from the two species 

 that have been just described in the fact that the setae, as in Geoscolex, become 

 separated by greater intervals posteriorly, being strictly paired anteriorly. The anterior 

 segments are annulate, as in T. gammii, and it is quite possible that there are no 

 differences between the two species in the number of the genital papillae ; these 

 structures vary so much in number in individuals that it is most unsafe to draw any 

 distinctions based upon apparent differences that they show. The calciferous glands 

 of this species, though agreeing with those of T. gavimii in being limited to a single 

 pair, are situated in a different segment, i.e. the eleventh or the twelfth. 



BoTJENE has stated that the sperm-duct opens into the muscular duct of the 

 spermiducal gland just before the latter penetrates the body-wall ; the penial setae 

 are remarkable for the fact that each sac contains setae of two kinds — a somewhat 

 unusual occurrence among the Oligochaeta, though seen in Acanthodrilus georgianus ; 

 some of the setae are smooth at the free extremity, others have the chevron-shaped 

 markings that occur in the penial setae of T. orientalis ; the caecal appendages of the 

 spermathecae are bifid or trifid. 



(4) Typhaeus laevis, Rosa. 

 T. laevis, Rosa, Ann. Mus. Civ. Genova, vol. ix (2 a), 1889, p. 388. 



Definition. Length, 35 mm.; number of segments, 180. Genital papillae, two pairs on XVII 

 and XVIII. Sab. — Burmah ; Ceylon, 

 This species is only very imperfectly known ; nothing with regard to the internal 

 characters is contained in Rosa's (8, 11) account of the species. It is to be 

 distinguished from the three foregoing by its smaller size and by the characters 

 of the papillae. In addition to these distinguishing marks the present species seems 

 to differ by the arrangement of the setae ; the two setae of the dorsal pair are 

 separated by wider intervals than are the setae of the ventral pair. Dorsal pores 

 were seen from the intersegmental groove xii/xiii. 



(5) Typhaeus foveatus, Rosa. 



T. foveatus, Rosa, loc. cit., p. 389. 

 Befinition. Length, \%o mm.; number of segments, x^o. No genital papillae. Penial setae 

 with minute points irregularly arranged upon the free end. Hob. — Rangoon. 

 This species is not well known; it is not easy to distinguish it from the last; 

 the specimens examined by Rosa were immature; the absence, therefore, of genital 



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