MARINE BIOLOGICAL STATION AT POET ERIN. 179 



There are, on the other hand, some organisms, such as 

 the Algre Halosphcera and Tetraspora, the Infusorian 

 Noctiluca, and the Copepod Anomalocera , which seem to 

 vary greatly in their abundance from year to year ; but 

 probably when we have a more complete knowledge of 

 the plankton of the North Atlantic, and of the relations 

 existing between physical conditions and the distribution 

 of organisms, we shall be able to assign rational causes 

 for these curious irregularities in the floating population 

 of our seas. 



We have arranged that in 1898 gatherings will be taken 

 weekly at the same six stations, but rather further out at 

 sea, so as to avoid the disturbing influence of the shore. 



It is interesting, in this connection, to note that of all 

 the tow-net gatherings which I took this summer in 

 crossing the Atlantic twice, between Liverpool and 

 Quebec, once at the beginning of August, and again at 

 the end of September, those from the sea around Port 

 Erin, between Liverpool bar and the north of Ireland, 

 were the richest in species. The following are the lists 

 of organisms observed in the gatherings in question, 

 quoted from the paper recently published by Herdman, 

 Thompson, and Scott* : — 



[Outward Journey — Liverpool to Quebec] 



"1. August 5th, 9 p.m., to August 6th, 8 a.m. From 50 

 miles off Liverpool to about Bathlin Island, Ireland. 

 Water slightly phosphorescent; no Ceratium observed; 

 an ordinary Irish sea gathering, containing : — Fish eggs, 

 Gastropod larva), Limacina retroversa, Nyctiphanes nor- 

 vegica (small), Nauplei, and Zoeas (Crab), Amphipoda 

 (fragments), Philomedes interpuncta, Sagitta bipunc- 

 tata, Mitraria larva, Medusoids (small), Campanularians 

 * Trans. L'pooI. Biol. Soc, vol. XII., p. 33. 



