REPORT OF COMMISSIONERS OF INLAND FISHERIES. 197 



No. 26) was made up of selected individuals enabled it to gain at once 

 an advantage which was never again lost. On the other hand, many 

 instances have fallen beneath the observation of the writer in which 

 the majority of young larva, hatching from the eggs of certain lobsters, 

 M^ere peculiarly deformed, usually with respect to the thoracic ap- 



Among such lobsters are found great mortalities at the critical 

 molting periods, and although the writer was successful in raising a 

 few such individuals into the later stages, each successive molt was 

 accompanied by greater discomfiture until most of the specimens 

 died in later molting periods. Those that lived always remained 

 weak and undersized. There were, however, many lobsters which, 

 without showing any signs of malformation, were naturally small and 

 stunted, and whose rate of growth was extremely slow throughout 

 all stages upon which observations were made. This was true, 

 moreover, not alone'at times when the water temperature was low, 

 but even when all conditions seemed most favorable to a full and 

 rapid development. Leaving, for the time being, further considera- 

 tion of the influences of injury and food supply, it is our intention 

 to proceed directly to a brief discussion of the influence of temperature 

 and light upon the rate of development of the young lobster. 



XIII. The Influence of Temperature. 



It may be said that the rate of development of the lobster from 

 the beginning of embryonic life through the early adolescent stages 

 is, provided the food supply be adequate, more fully determined by 

 the prevailing temperature of the water than by any other one factor. 

 It has been shown again and again that the eggs which mature during 

 the colder part of the season and in cooler w^aters give rise to in- 

 dividuals which are distinctly undersized, and whose growth is corre- 

 spondingly slow throughout the remainder of the season. As Mead 

 ('02) has already clearly shown, the influence of the temperature is 

 most effective upon lobsters in the larval stages. In this regard the 

 following table is self-explanatory. 



