650 KEPORT OF THE COUNCIL. 



Dr. J. H. Orton gives an interesting account of the mechanism by means 

 of which the Brachiopods and certain Polychaete worms produce the 

 currents which supply these animals with food and with a supply of 

 water for respiration. The arrangement of the cilia, to the action of which 

 the currents are due, is carefully described, as is also the direction and 

 use of the different currents themselves. It is shown that the ciliary 

 mechanisms on the gills of many Gastropods, most Lamellibranchs, 

 Amphioxus, Ascidians, Brachiopods and Cryptocephalous Polycheetes 

 are essentially similar in character. 



In a second paper Dr. Orton gives an account of certain Holothurians, 

 which are common at Plymouth, describing in some detail the characters 

 by which they can be differentiated, and recording some observations 

 on their habits. Other papers by the same author deal with the breed- 

 ing habits of the sea-urchin, Echinus miliaris, the feeding habits of the 

 limpet. Patella vulgata, and with certain features of the life-history of 

 Amphioxus. 



Dr. Orton also gives a preliminary account of his work on the rate of 

 growth of invertebrates and the age at which they commence to breed 

 for the first time. This investigation when completed promises to be of 

 considerable importance from a practical as well as from a theoretical 

 point of view. 



The Council desire to congratulate Dr. Orton on attaining the degree 

 of D.Sc. at the University of London, which was awarded upon the 

 researches which he has carried out at the Plymouth Laboratory. 



The Journal also contains three papers by Prof. E. L. Bouvier, of the 

 Paris Natural History Museum, which are the outcome of the work 

 he did at the Laboratory as first " Eay Lankester Investigator " during 

 the summer of 1913. Prof. Bouvier's work on the life-history of the sea- 

 crayfish {PaUnurus vulgaris) was referred to in the Council's Report for 

 last year, and need not therefore be further described. His other papers 

 deal with observations on the Crustacean larva, Trachelifer, and on 

 variation in Pycnogonum littorale. 



During the first half of the present year Mr. Clark continued his 

 investigations on the mackerel fishery off the Cornish coast. A con- 

 siderable body of valuable information has been collected bearing on the 

 migrations and feedmg habits of this fish. The work upon larval and 

 post-larval fishes was also continued. 



Mr. D. J. Matthews has been studying the chemical composition of 

 Bea-water, devoting himself for the most part to the elaboration of a 

 method for the accurate estimation of the nitrates. 



