844 ALFRED GIBBS BOURNE. 



1. N. elinguis, O. F. Miiller. 

 This species is common in England. 



2. N. barbata, O. F. Miiller. 

 This species is common in England. According to Semper^ 

 the budding zone appears after segment xvii in this species 

 (i.e. n, as used on page 339, is equal to 17). 

 3. N. josinae, Vejdovsky. 

 I have not seen this species. 



4. N. fusca, Carter. 

 This species is recorded from India^ but is not sufficiently 

 characterised. 



5. N. scotica^ Johnston; England. 

 Not sufficiently characterised. 



B oh e mi 11 a, Vejdovsky (see woodcut). 



Three cephalized segments in addition to the peristomial 

 segment remain well marked in the fully grown head. 

 There is no prostomial tentacle. 

 The capillary dorsal setse are serrated. 

 There are no branchial processes. 

 Eyes are present in the only known species. 



1. B. CO mat a, Vejdovsky. 

 (Syn. Nais hamata, Tiram.) 



I received numerous specimens of Bo he mill a from Mr. Bol- 

 ton. It has not been, I believe, hitherto recorded from Eugland. 

 The specific characters agree very closely with those given by 

 Vejdovsky and Timm. I never found a specimen without eyes ; 

 Vejdovsky makes no mention in his large book of their 

 presence or absence, but Timm states that the eyes are not 

 always present. I have noticed that the pigment in the 

 alimentary canal commences in the region of the first dorsal 

 seta bundle in this and many other species of Naids. 



The uephridia are not present in all the segments. 1 

 observed nephridia in segments viii, xi, xvi, xviii, xx, and 

 XXI, each with a funnel opening into the segment in front. 

 ' *Arb. zool. zoot. lustitut. Wurzburg,' Bd. iv, 1877. 



