MARINE BIOLOGICAL STATION AT PORT ERIN. 33 



second and third stage larvae. I now Lad great hopes that we 

 were within reach of a more substantial advance than we had 

 hitherto attained. A few days later, however, we noticed that 

 the larva?, especially those in the third stage, were disappearing, 

 and on draining off most of the water from the pond, their 

 decomposing remains were found in numbers on the bottom. 

 I cannot offer any explanation of this. Large quantities of 

 water were pumped into the pond daily ; and all unconsumed 

 food was removed as thoroughly as possible. After this the 

 newly hatched larvae were removed from the pond every 

 morning, counted, and placed in the hatching boxes. This, 

 of course, added considerably to T. Monaghan's work. Accord- 

 ing to a statement which he left with me he dealt with 3,943 

 larvae, of which 10 reached the lobsterling stage before he left 

 on August 9 th. 



" Mr. A. E. Kidd, also from the Liverpool University 

 laboratory, began work on August 11th and left on Sept. 4th. 

 On the lines described above he dealt with 4,038 larvae ; and 

 on the date of his departure 120 lobsterlings had been set free. 

 During the second week in September the eggs of the lobster 

 placed in the pond on the 3rd of that month began to hatch out, 

 and I took the earliest opportunity of transferring 1,000 — all 

 but a very small number of them — to the hatching boxes. 

 In spite of the devotion of many hours to the care of them, 

 only eleven have reached the lobsterling stage. Though 

 the conditions, temperature, &c, have remained much the same 

 as they were in the late summer, the development of these 

 larvae has proceeded at a slower rate than that of those dealt 

 with by Messrs. Monaghan and Kidd. I fed them daily on 

 minced mussel (Mytilus edulis), and satisfied myself that they 

 partook of it. In addition to this food I found that Copepoda 

 were constantly present in fair numbers in the water flowing 

 through the hatching boxes, so that there can be no question 

 of the larvae having died for want of sufficient food. 



