86 W. BLAXLAND BBNHAM. 



structure the rostellar apparatus agrees with that described 

 for T. undulata by Leuckart (see Bronn, p. 1327), but 

 differs in some details. It is described at the end of the 

 present paper. 



As to the systematic position of this Cestode, I speak with 

 some diffidence, since I have no recent literature, beyond a 

 few manuscript notes on anatomical points, to aid me in the 

 determination. Bronn's 'Thierreich' has not yet reached 

 the systematic account of the group. But the worm appears 

 to belong to Raillet's genus Drepanidotsenia — a charac- 

 teristic genus of avian parasites. 



But the number of booklets on the rostellum is greater 

 than in those species to which I can find reference ; ^ and, 

 moreover, they are in two closely placed circlets instead of 

 the "single circle" given as a character of the genus. 

 The hooks themselves are larger, and apparently the parts are 

 better marked than in other species. 



It may be a representative of a distinct genus, but pro- 

 visionally I name the worm Drepanidotsenia rainuta, and 

 characterise it as follows : 



A tetracotylean Cestode measuring about To mm., with 

 nearly parallel sides, consisting of a very few (about a dozen) 

 proglottids, of which the last alone contains ripe eggs. The 

 scolex is much flattened ; the suckers are provided with flaps 

 (or valves), so that the entrance appears reduced. The ros- 

 tellum is complex ; the hooks, in two closely set circlets, are 

 eighteen or twenty in number ; each hook measures 0"04 mm., 

 and has the usual parts well marked, the "handle" being 

 much longer thau the " guard." There is practically no 

 neck; the proglottids are short and wide; the genital pores 

 are alternate. The ripe eggs measure 0'03 mm. Hab., intes- 

 tine of Apteryx Bulleri. 



Remarks. — The small size of the strobila and the fewness 



of its proglottids render this worm rather remarkable, for it 



is one of the smallest species of Cestodes. Amongst the 



Tetracotylea (the family Tasniadee in the wide sense) there 



1 Shipley, "On Drep. he mi gnat hi," 'Quart. Jouru. Micr. Sci.,' xl, p.613. 



