352 MR. F, E. BF.DDARD ON [May 3, 



» 



called it — evidently by a slip of the pen — " Molosoma lacteum. 

 I have lately examined a single specimen of an Molosoma which I 

 refer to this species. Unfortunately I am not able to fix its locality 

 with accuracy, as I found it in a bottle containing water and weeds 

 from various sources. 



Leydig himself was of opinion that the species might turn out on 

 further study to be an immature stage of ^. hemprichii, or of 

 some species with coloured oil-drops in the integument ; but he 

 quoted, as against this possibility, Ehrenberg's observation that the 

 red colour is visible in embryos still within the egg, and was there- 

 fore, on the whole, inclined to regard the worm as an adult form of 

 a species with a colourless integument. 



I have, however, recently pointed out that ' the supposed cocoons 

 are in all probability merely cysts into which I he worms can tem- 

 porarily withdraw themselves ; so that Leydig's opinion as to the 

 possibility of his ^olosoma niveum being an immature form is not 

 necessarily rendered untenable by Ehrenberg's observations. 



Vejdovsky ^ in describing briefly the characters of his new species, 

 ^olosoma variegatum, remarked that it was " hothst wahrscheinlich 

 von Leydig beobachtet und als ^■Eolosoma niveum beschrieben." 

 In a fuller account ^ of ^. variegatum Vejdovsky establishes its 

 distinctness from ^olosoma niveum ; it agrees, however, with that 

 form in possessing some colourless oil-globules in the epidermis, the 

 rest being green. In ^olosoma niveum all the integumental oil- 

 globules are colourless. 



The most recent remarks upon Leydig's ^olosoma niveum known 

 to me are to be found in Vaillaut's account of the Oligocheeta in the 

 ' Suites a Buffon.' In that work Vaillant considers it to be not yet 

 established that the supposed species is not the young form of some 

 other ^olosoma. I am therefore particularly glad to be able, 

 I think, to definitely settle this question. 



I had on the same slide and under examination at the same time 

 no less than three species of .^o/oso/wa — an experience which is not, 

 I imagine, very common. These species were, ^. quaternarium, 

 ^. niveum, and a species of whose identity I am not quite certain ; 

 it was as large as my JEolosoma headleyi *, but may be JEolosoma 

 variegatum; I lost sight of it before I completed the examination. 

 The worm which I believe to be ^olosoma niveum is at any rate 

 a perfectly distinct species from any known to me. It comes nearest 

 to ^olosoma niveum as described by Leydig. Nevertheless, it does 

 not altogether agree with his description. It may therefore con- 

 ceivably be a new form. It was fully as large as J^. quaternarium, 

 and there are other reasons for believing that it cannot be the young 

 of that, or indeed of any other known species. 



1 " Note upon the Encystment of Molosoma," Ann. Mag. Nat. Hist., Jan. 

 1892. 



^ System und Morph. d. Oligochaeten : Prag, 1884, p. 113 footnote. 



^ "Molosoma variegatmn, Vejd., Prispevek ku poznani nejnizsich Annulatuv," 

 SB. bohm. Ges. 188o. 



" "Observations upon an Annelid of the Genus J?ofosowi«," P. Z. S. 1886, 

 p. 213. 



