322 DAVID BEYCE ON 



These tliree Adinetae are quite cosmopolitan. A. vaga occa- 

 sionally occurs in pools, but, like the others, is a common 

 inhabitant of mosses. 



Ceratotrocha cornigera (Bryce). 

 Since the original discovery of isolated examples of this rather 

 rare species in England, it has been found to be widely distri- 

 buted. It has now been recorded from Scotland, Switzerland, 

 Canada, Australia, and Peru. 



Hahrotrocha constricta (Dujardin). 

 One of the commonest of the pellet-making Philodinidae, and 

 widely distributed. 



Hahrotrocha elegans (IVIilne). 

 In my earlier report (1), I described the specimens obtained 

 from Dr. Gregory's collections under the name Callidina venusta, 

 sp. nov. The species having since been transferred to the genus 

 Hahrotrocha, Milne's original specific name has again become 

 valid and replaces venusta. 



Hahrotrocha insignis Bryce. 



The few specimens which I have assigned to this species 

 differed from the type form in showing very indistinctly the 

 curious hardened plate in the head which I thought to be a 

 stiffening for the upper lip, and which I have hitherto found to 

 be somewhat conspicuous. In some examples I could detect 

 no trace of it. Otherwise the specimens agreed with the British 

 form. 



Hahrotrocha Milnei nom. nov. (fig. 5). 



I take this opportunity to put forward a new name in place 

 of one given earlier by Milne, when in 1886 he described a pellet- 

 making rotifer closely allied to Hahrotrocha constricta (Dujardin), 

 but having only two teeth on each ramus, under the name of 

 Macrotrachela hidens. In my revision of the classification of 

 the Bdelloida (1910) * this species should have been assigned to 

 the genus Habrotrocha then created for the reception of all 

 but the most aberrant of the pellet-making forms. But un- 

 fortunately the specific name hidens had been already employed 

 for Gosse's still older Callidina hidens, which was also to be 



* Bryce, D., On a New Classification of the Bdelloid Rotifera, 

 Journ. Q.M.G., 2nd Ser., vol. xi., pp. 61-92. 



