Mollusks. 7209 



R. parva {Rissoa alba, Cingiila parva). Abundant. Va?'. R. in- 

 terrupta, abundant. Peculiarly characteristic specimens are to be 

 found in rock pools at Farland Point, Cumbrae. 



R. costulata. Laralash, Landshorough. 



R. rufilabrura. Abundant on Zostera marina growing in the large 

 rock pool on the Allans, Cumbrae; and also found, though less com- 

 monly, in similar situations at Lamlash, and probably throughout the 

 district. 



R. labiosa [Turbo labiosus, Cingula labiata). A few examples 

 dredged in Kames Bay, Cumbrae. A large fragile form, abundant on 

 the large Zostera beds near the Pier at Lamlash ; Bute, Ayr ; 

 Smith. 



R. inconspicua. Frequent dead and worn in Lamlash Bay. 

 Occasionally found also alive on decaying Laminariae and in rock 

 pools. 



R. tenuis {Alder). Mr. Alder is still firm in the conviction that 

 the Rissoa inconspicua, var. c. of Forbes and Hanley, is a distinct 

 species. The shell was first taken by him " at and a little below low 

 water-mark at Rothesay," and he has since received it from Shetland. 



R. Goodallii {Alder, MS.). I found a small Rissoa in company 

 with R. rufilabrum at the outer Allans, which is referred by Messrs. 

 Hanley and Jeffreys to R. inconspicua, of which species they 

 consider it a dwarf form. Mr. Alder thinks it may be distinct, but 

 adds " I should like to see the animal before making up my mind. 

 The shell does not show any of the delicate markings usually found 

 on R. inconspicua. The manuscript name of Goodallii in my 

 cabinet was attached to them because I got the first specimens from 

 Bean, who had received them from Dr. Goodall under the name of 

 Turbo vittatus (a synonym of T. cingellus), and knowing they did 

 not belong to that species, I attached the Doctor's name to them for 

 distinction's sake." — Alder in lilt. To this observation of Mr. Alder, 

 I may add that I have myself seen this shell in cabinets erroneously 

 labelled " Rissoa vittata." 



R. semistriata. Lamlash, Landsborough. 



R. cingellus {Rissoa vittata, Turbo cingellus). Not uncommon 

 under stones near low water at many places in the district. 



R. vitrea {Turbo vitreus). Lamlash, Landsborough ; Ayr, Smith. 



R. fulgida. I have procured a specimen or two in Kames Bay, 

 Cumbrae, and also found the species at Lamlash. 



R. rubra. Included in Dr. Landsborough's latest revised Cata- 

 logue of the Lamlash Bay Mollusca. 



XVIII. 3 H 



