MARINE BIOLOGICAL STATION AT PORT ERIN. 21 



Cladocera were represented by Evadne 

 nordmanni, Podon intermedium, and Podon 

 leuchartii. These were only observed in the 

 collections taken during May and June, 1903, 

 and May, -Tune, -Inly, September, 1904. Podon 

 leuchartii, G. 0. Sars, has not previously been 

 recorded from the L.M.B.C area. 



The Larval stages of some of the Crustacea 

 at certain times of the year make up a consider- 

 able portion of the surface plankton. The 

 following are the most prevalent : (a) Copepod 

 Kauplii — these were only absent during July, 

 October, November, December, 1903, and July, 

 1904. (b) Cirripedia larvae. The Nauplii of 

 barnacles are sometimes so abundant that tow- 

 nettings taken in the spring appear to consist 

 of little else than these larvae. They were 

 only observed in April and May, 1903 and 1904. 

 The " Ostracod " stage were found in May and 

 June, 1903 and 1904. (c) Crab " zoea " 

 occurred during April, May, June, July, 

 August, September, 1903, and April, May, 

 June, 1904. The " megalopa " were present 

 during July, August, September, 1903, and 

 September, 1904. (d) Larval Crangon were 

 noted for May, June, July, August, Sep- 

 tember, 1903, and April, May, June, July, 

 August, 1904. 



8. TUNICATA. 



Oikopleura was observed in the tow- 

 nettings taken during May, June, July, 

 October, 1903, and February, April, May, 

 June, July, August, September, 1904. The 

 eggs of Ascidians were only found once, 

 February 10, 1904. 



