OLDHAM : NOTES ON SOME ANGLESEA MOLLUSCA. 89 



P. milium. — Ditch near Camlyn Bay. Llynfelinant and Llyn- 

 llygeirian. 



In 1 891 and 1892, I collected some shells in the neighbourhood of 

 Rhos Neigir, on the south-west coast, near Holyhead, and met with 

 the under-mentioned forms, which I did not obtain at Cemmaes. 

 There are in this district several lakes fringed with reed-beds and belts 

 of water-lilies, which are better adapted for aquatic species than those 

 near Cemmaes. The long stretch of sand dunes in Cymmeran Bay 

 also affords somewhat different conditions to the rocky coast of the 

 north of the island. 



Helix pulchella. — Sand dunes near Rhos Neigir. 



H. itala. — Sand dunes, Cymmeran Bay. 



H. acuta var. bizona. — With the last. 



Pupa muscorum. — Sand dunes near Rhos Neigir. 



Planorbis nautileus. — Small pond near Llyn Penryngwylanod. 

 Var. crista. — With the type. 



Limnaea stagnalis. — Llyn Maelog. 

 Var. fragilis. — Llyn Main. 



Velletia lacustris. — On leaves of Nymphcea and Nuphar'm Llyn 

 Penryngwylanod. 



Anodonta anatina. — Llyn Maelog and Llyn Penryngwylanod. 



Mr. J. G. Milne, who has also collected at Rhos Neigir, notes the 

 following : — 



Helix pygma^a. — Llanvaelog Common. 



Physa fontinalis var. albina.— Llyn Main. 



Ancylus fluviatilis var albida. — Llyn Maelog, with the type. 



Sphaerium corneum var. flavescens. — Llyn Maelog. 



Paludestrina jenkinsi near Middlesbrough. — In the early spring of 1897 

 I found some exquisitely constructed caddis cases made of the empty valves of P. 

 jenkinsi, in a beck, between Thornaby ar.d Middlesbrough. Last summer I 

 visited the neighbourhood again, and found a few immature living specimens of 

 P. jenkinsi on the Elodea canadensis. Later, in the autumn, I thoroughly investi- 

 gated the same stream, and discovered in a bend sheltered by a luxuriant growth 

 of Arundo phragmites, a large colony of fully-developed specimens. They were 

 literally crowded together. With each draw of the collecting-scoop I was able to 

 secure twenty or thirty individuals. They were found in company with Planorbis 

 umbilicatus, Physa fontinalis, and Limncea peregra. So far, the var. carinata has 

 not been seen, all the specimens being uncarinated forms. The beck named flows 

 into the river Tecs, and I note the conjecture of Mr. L. E. Adams, in his admirable 

 Manual, as to the shells being imported in Baltic timber. On inquiry, I have ascer- 

 tained that Baltic timber is constantly brought into the Tees, and it may be that 

 the colony I have found has been imported in this way to this locality. — A. Hann, 

 Thornaby, April 16th, 1898 (Read before the Society, May nth, 1898). 



