a2 MR. F. E. BEDDARD ON ZOLOSOMA TENEBRARUM. [Feb. 5, 
Soc. 1888, p. 213). I am also able to take this opportunity of 
announcing the occurrence in Ireland of Vejdovsky’s species Holo- 
soma variegatum (‘ Alolosoma variegatum, Prispevek ku poznani 
nejnizsich Annulatuv,’ SB. béhm. Ges. Wiss. 1885), of which some 
examples were kindly forwarded to me by Prof. Howes, who had 
himself received them from Prof. Hartog, of Cork. A comparison 
of &. tenebrarum with 4. variegatum has convinced me that, as I 
stated in my paper, the affinities of 4. headleyi are with the latter 
species. In both these forms the epidermic coloured cells are bright 
green, while in . tenebrarum they range from greenish yellow to 
brownish olive. 4. tenebrarum, furthermore, differs from all other 
species of the genus in possessing J-shaped setze in the posterior 
segments of the body, in addition to the hair setee present in those 
segments and elsewhere: the sete are stated by Vejdovsky (loc. cit.) 
to be bifid at the free extremity, but I have not been able to see this 
in my specimens ; in Vejdoysky’s specimens the epidermic coloured 
cells are of a pale yellow, contrasting therefore with the specimens 
studied by myself, which I am unwilling, however, to refer to a new 
species since they agree in all other particulars with 4. tenebrarum. 
This species of Molosoma is extremely hardy if supplied with 
sufficient food. I have a large number of specimens which go on 
multiplying rapidly in a small bottle containing duckweed and a thin 
layer of vegetable débris at the bottom ; the worms have remained 
in this small vessel for several months, although there is a tolerably 
thick scum of Leptothriz and Bacilli upon the surface. 
On the other hand, if deprived of food they soon die; three 
specimens placed in a watch-glass containing water from the vessel in 
which they lived, but no appreciable quantity of vegetable débris, 
died in an hour and a half. The watch-glass was placed on a 
window-sill of north aspect. In these particulars 4. tenebrarum 
contrasts with 4. variegatum. I placed the specimens of the latter 
species in a bottle with abundant food ; the water and the duckweed 
were obtained from a locality where there were no specimens of 
42, tenebrarum; one or two examples of the latter were, however, 
introduced by means of a pipette; these multiplied to a great 
extent, and I have not been able since to discover a single specimen 
of &. variegatum. 
The green-coloured spots of 4. tenebrarum are large cells with a 
thin peripheral layer of protoplasm containing a nucleus; in the 
centre is a large globule of oily appearance impregnated with the 
colouring-matter. Vejdovsky has remarked (loc. cit. p. 65) that 
the globule is stained black with osmic acid, thus proving it to be 
of an oily nature. I have found that osmic acid produces a dark 
brown stain. 
The green colouring-matter naturally suggests chlorophyll; and 
Zacharias (“‘ Studien tiber die Fauna des grossen und kleinen Teiches 
im Riesengebirge,” Zeitschr. wiss. Zool. Bd. xli. pp. 499-500) states 
that in an olosoma (probably 4. variegatum) he observed the 
green bodies dividing, and therefore considers that they may be 
parasitic alge. With a view to discovering whether the bodies 
