MAKINE BIOLOGICAL STATION AT PORT ERIN. 299 



work on the Acarina. We have found the home of this 

 species to be deep in the cracks and fissures of the chffs 

 round the Biological Station. From these holes the mites 

 occasionally emerge in numbers, and are then found over 

 the shore and on our concrete steps. 



Mr. Chadwick made a special study of the plankton of 

 Port Erin Bay during part of May, and collected a large 

 amount of material, which is not yet fully examined. He 

 found, amongst other things, various stages in the life 

 history of Amphicocloii fritillaria, post larval stages of 

 Pohjnoe, Terehella, and Pectinaria, and also the Hali- 

 stemma-like Siphonophore, which had been found by Mr. 

 E. T. Browne in April. 



Professor Weiss was at work during the spring at Port 

 Erin, on Marine Botany. In part he was investigating 

 the effect of different coloured lights on various living 

 sea-weeds. He did not arrive at any definite result, but 

 intends to pursue the matter further. He also spent 

 some time in examining living Diatoms, with a view to 

 clearing up some imperfectly known particulars in their 

 life history. This work is also not yet completed. 



Miss L. K. Thornely and Miss K. Alcock worked 

 together at the Station for some time in June. Miss 

 Thornely was occupied with the collection and deter- 

 mination of Polyzoa, and Miss Alcock was preserving 

 material for investigations on the microchemistry of the 

 tests of Tunicata. 



In September we obtained some specimens of Calocaris 

 with ova on the abdomen. The ova are of a pale red 

 colour, and of relatively large size, measuring about 1'5 to 

 2 mm. in diameter in a specimen about 5 cm. long. There 

 are from 45 to 60 ova on each individual. It is interesting 

 to compare these measurements with those of the common 

 shrimp, where an individual 7 cm. long may have about 



