[44] MR. JAMES RITCHIE OX HYDROIDS [May 28, 



Family SEBirLAEiiD^. 



Sertularia distans Larax. 1816. 

 „ mai/eri Nutting 19l>i. 



„ vershtysi Nutting 1901. 



„ l(evimarghiata, sp. n. 



Family PLUiitrLiEiiB^. 



l^lumufaria halecioides AlJer 1859, 

 Monostachas qtuidridens (McCrady 1857). 

 Aglaophenia marginata, sp. n. 

 Lytocarpus grandisj var. unilateralism viir. n. 

 „ crosslandij sp. n. 



Of the 18 hitherto known forms above mentioned, 10 arerecog- 

 niseil as Briti.sh species, while 5 of the remainder (Campanularia 

 ptychoci/athus, Sertularia mayeri, S. verslwjsi, Lytocarjyus grandis, 

 iionosiischas quadridens) are, with the exception of tlie last 

 which has been recorded from the Indian Ocean (Thornely, 1904), 

 distinctively American. This contingent is probably to be ac- 

 counted for by the oceanic whirlpool the centre of which is marked 

 by the Sargasso Sea and the streams of which wa.sh the shores of 

 the West Indies, of eastern Mexico, and of the eastern United 

 States, and, circling in the North Atlantic, sweep past the 

 Azores, Madeira, and the Cape Verde Islands. 



The collection, as might be expected in a littoral one, is com- 

 paratively rich in gymnoblastic forms and includes an interesting 

 species, peculiar in branching and in gonophore, which has been 

 made the type of a new genus, Soleniopsis. 



We note also, as Pictet has alre;xdy remarked (Pictet, 1893), 

 that of those species which occur both in temperate and in tropical 

 waters, the individuals existing in the colder seas are, in general, 

 larger and more sturdy than their ti'opical specific equivalents. 



The outlines of the figures, both in the plates and in the text, 

 with the exception of those representing the appearance of the 

 specimens to the unaided eye, were drawn with the help of Zeiss's 

 camera lucida. 



The localities from which ]\[r. Crossland obtained his specimens 

 are shown below : — 



ST. VINCENT, CiPE Verde Islasds. 

 (1) Geseeal. 



(a) From tidal pool, 25th July, 1904. 



Pennaria cavolinii Ehr. 

 (6) 2 fathoms, among coral, 22iid July, 1904, 

 Fenymria cavoJinii Ehr, 

 Sertularia mai/eri Nutt, 

 Flumularia halecioides Hincke. 



(c) 10 fathoms, 27th July, 1904. 



Gonothifr<sa gracilis Sars. 

 Campanularia ptychocyathus AUm. 



(d) 15 fathoms, 30th July, 1904. 



Monosfachas quadridens (McCrady). 

 Jjt/tocarpus grandis, var. unilattralis, var. n. 



490 



