SEA-FISHERIES LABORATORY. 93 



Mr. W. C. Smith, and scales have been preserved for future 

 study. A series of chemical analyses of the flesh and liver 

 of Port Erin cod has also been made on samples obtained every 

 few weeks, and it is hoped that these will fit into a bigger 

 scheme of investigation of the seasonal changes in the meta- 

 bolism of marine animals and plants in the Irish Sea area. 

 The changes in general " condition " of the fish during the 

 season have also been observed, and other lines of investigation 

 will, no doubt, present themselves later on. 



The Chemical Composition of the Mussel. 



A preliminary study of the chemical composition of the 

 common mussel has been undertaken by Mr. Daniel, and the 

 results of this are published in the tables given on pp. 281-285. 

 As this investigation has proceeded many interesting questions 

 have been suggested — the nature of the substance which is 

 called "glycogen," for instance. It cannot be doubted that 

 this is not the same, chemically, as the glycogen of the warm- 

 blooded animal, and difficulties and anomalies encountered in 

 the course of the work suggest that an exhaustive research 

 on the nature of the carbohydrates found in molluscs is very 

 desirable and may be of economic value in view of the further 

 utilisation, in some form or another, of the organic material 

 found in mussels. The use of the molluscs as human food, 

 in the fresh condition, has been decreasing for years past 

 because of the somewhat bad reputation they have now 

 received from the Public Health Authorities, and, as things 

 are, their total exclusion from the food markets seem only 

 to be a matter of time. Year by year, for instance, an increas- 

 ing fraction of the great Morecambe supply goes to the East 

 Coast as bait for the liners, and until a good method of cleansing 

 them from sewage pollution can be generally applied this 

 tendency will continue. We have to reckon, then, on finding 

 some new use for the huge supply of material which the 



