SEA-FISHERIES LABORATORY. 20 1 



on our Forms will probably well repay analysis, bnt these 

 must now be left over for another occasion. 



Cladocera. 



The two species of this group found in our district, 

 Podon intermedium and Evadne nordmanni, occur mainly 

 in summer, in a wide sense, ranging from the end of 

 March to the beginning of October. Our first record of 

 Podon is six specimens on March 26th, and the last is 

 fifty on October 9th. Evadne begins with ten on March 

 29th, reaches 500 on April 9th, and ends with 50 on 

 September 20th. Tens, twenties and thirties are common 

 numbers in the records of both species, but sometimes the 

 hundreds are reached. As a rule there is no great 

 difference between surface and deeper hauls, and 

 occasionally there is great constancy of results, indicating 

 an even distribution :— e.g., on April 18th at Station II. 



At Station II. Surface nets. 10 faths. Shear. 



Podon intermedium 150 150 — — 



Evadne nordmanni 100 100 150 50 50 



On April 19th, in the bay, two similar surface hauls 

 took 40 and 37 Podon, and 75 Evadne each; and at the 

 same time, at Station II, ten miles oft', the two surface 

 nets took 40 Podon and 75 Evadne each. Other similar 

 cases might lie quoted ; but on the other hand there are 

 diverse hauls on other dates showing a very uneven 

 distribution. The numbers during May and June are 

 relatively high : — 



Podon 



Evadne 



This is the highest point reached by Evadne, and this 

 form is practically absent, or only occasionally present, 

 during the latter half of August and parts of September. 

 Podon reaches a climax (500) rather later, on August 



190 



so 



150 



100 



100 



150 



60 



so 



300 



300 



300 



650 



