MARINE BIOLOGICAL STATION AT TORT ERIN. 33 



parasite was discovered in Port Erin whelks fourteen 

 years ago, by Jameson, and it does not seem to have been 

 recorded elsewhere. It is interesting to find it turning 

 up still in the same place. Jameson states that it occurs 

 in tlie kidney and kidney duct, but those that I have 

 found were always in the stomach and rectum. As the 

 kidney opens directly to the exterior I cannot quite 

 understand what Jameson meant by kidney duct. 



" Most of the detailed work on the anatomy of the 

 whelk has now been completed, and I hope to have the 

 MS. ready for publication in January." 



During part of the Easter vacation Miss M. 

 Latarche, B.Sc, made a preliminary bio-metrical 

 investigation of the variation in the shells of the common 

 limjiet {Patella culgata). These were taken from three 

 different localities, viz.: — Port Erin, Eleshwick Bay 

 and Port St. Mary. 



Comparisons were made between sets of shells 

 taken — 



(1) From high and low water marks; 



(2) From Carboniferous limestone and Cambrian 



slate ; 



(3) From more exposed and more sheltered waters. 

 The variation occurred chiefly in the height of the 



cone compared with the breadth. The shells of those 

 taken from about low-water mark were found to be much 

 flatter than those taken from near high-water mark. 



The nature of the rock on which the Patellae lived 

 did not affect the height of the shells. Those found on 

 the limestone at Port vSt. Mary were more markedly 

 ridged and were of a lighter colour. Intermediate links 

 between these and the darker, smoother, shells of Port 

 Erin were found to exist in both localities. 



