Aquatic Oligochaeta from Japan and China. 
93 
anderes als einfache Ausstulpungen der Hypodermis, in die eine Schleife des integu- 
mentalen Blutgefass-Netzes mit liineingezogen ist. Das sind keine Bildungen von 
morphologisch sehr bedeutsamen Charakter"; and again in the same paper "(the 
gills) hochstens artliche Bedeutung haben ; sind sie doch nur eine Anpassung an die 
Sauerstoff-Armut warmer stagnierender tropischer Gewasser." However he later 
(14) places the presence of gills among the generic characteristics of Branchiura; and 
in another family, the Naididae, gills of the same kind as those of Branchiura are 
well recognized as constituting a character of generic value {Branchiodrilus, Dero, 
Aulophorus) ; a Dero without gills would be aNais. 
The presence of a penis however (as distinguished from a pseudopenis, which 
arises by evagination of the simple tubular end of the atrium, and disappears on re- 
traction) is certainly of considerable importance (Michaelsen, 13), and a character of 
generic value. I think therefore that there can be no doubt that the present form 
is to be separated from Branchiura, though this is pretty certainly its nearest rela- 
tion; and I name it after Dr. T. Kawamura, the zoologist in charge of the Otsu Lake 
Laboratory. 
The affinities of Branchiura to other genera have been touched on by Michaelsen 
(13). He supposes a close relationship to Bothrioneurum. Both fall into the section 
of the Tubificids which are characterized by the possession of a diffuse ' ' prostate ' ' 
covering the vas deferens (or part of it) ; and both are included in the much narrower 
section which possesses a paratrium. The only essential difference between the two 
is, according to this author, the presence of gills in Branchiura and their absence in 
Bothrioneurum; and he doubts whether this is sufficient to justify a generic separa- 
tion C'ob der Besitz von Kiemen ausschlaggebend fur die generische Absonderung 
der betreffenden Arten sein darf, will mir zweifelhaft erscheinen " ). But Michaelsen 
omits to mention the absence of spermathecae in Bothrioneurum , and the presence of 
spermatophores (which are probably characteristic for the genus, though not yet 
demonstrated for B. americanum, cf. Beddard, 3). And if it is true, as suggested 
above, that Branchiura is descended from ancestors which possessed a penis {Bothri- 
onettrum presumably never had one), the distinction between them is still further 
widened. The coelomic sac, at any rate, constitutes an additional feature of Bran- 
chiura which is not found in Bothrioneurum. 
There can of course no longer be any question of an affinity between Branchiura 
and Taupodrilus , with which, prior to the discovery of the paratrium, it was confused. 
Limnodrilus socialis, Stephenson. 
In ditches round the city of Kyoto, Japan; sold as food for goldfish. Numerous specimens. 
In 1899 Hatai (6) published the description of a worm found in Tokyo, which he 
called Limnodrilus gotoi. In 1912 I published (16) an account of a species of Limno- 
drilus which I called L. socialis; the worm is common in Lahore, and later in the 
same year I recorded having received it from Calcutta (17); subsequently it was 
found in a collection made by Annandale in Ceylon (18). In 1913 Nomura (16), 
