PLANKTON FROM NEW BRUNSWICK. 285 



with the basal lobe of the right outer seta enlarged to form a 

 conspicuous process upon the right ramus. Professor Ramsay- 

 Wright found it exceedingly common at Canso from the end of 

 July to the middle of August ; he offers an explanation of the 

 asymmetrical tail based u23on the mode of attachment of the 

 spermatophore {op. cit. p. 14). This is very likely correct, but I 

 cannot confirm the statement that the asymmetry is greater in 

 the female than it is in the male. It was not so in my obser- 

 vations at St. Andrews. The species was originally described 

 from the Gulf of St. Lawrence in 1897 (I, C. Thompson and 

 A. Scott, " J^otes on new and other Copepoda in Plankton col- 

 lected continuously during two traverses of the North Atlantic," 

 Proc. and Trans. Liverpool Biol. Soc. vol. xii. 1898, pp. 71-82, 

 pis. 5-7). It was again described as Corynura humpusii by 

 W. M. Wheeler, from Woods Hole a.nd Vineyard Sound {pp. cit. 

 1901). L. W. Williams {op. cit. 1906) first suggested the identity 

 of Corynura bumpusii with Tortanus discaudatus ; but he de- 

 scribed an allied form, abundant in Naragansett Bay and 

 Charlestown Pond, as a new species, T. setacaudatus, differing 

 from discaudatus, as it would appear, chiefly in the character of 

 the fifth legs in the female, which cai'ry spines in the former and 

 are without spines in the latter species. The eye of T. discau- 

 datus resembles that oi Acartia clausi and quivers in like manner. 

 It would be worth while to make a biometrical study of its 

 remarkable caudal furca. Length of c5' 1*75 mm. 



Eiiryteinora herdmani Thompson and Scott, is to be distin- 

 guished from allied species of the genus, especially from E. hiruti- 

 doides, b}^ the structure of the fifth legs in the female. Females 

 with ovisac were noted on August 12th; and on the same date, 

 males with the tumefied central part of the right antenna scarlet. 

 L. W. Williams {op. cit. 1906) recorded tliree species from the 

 Rliode Isla,nd region : E. americana, sp. n., E, hirundoides, and 

 E. herdmani. 



The ebbtide plankton of August 9th was largely composed of 

 Chcetoceras and Rhizosolenia, Tintinnoids, Synchceta, Acartia, 

 Na.uplii, some Fritillai-ia borealis, and the Cladocera : Evadiieund 

 Fodon. Podon occurred in almost every tow, and often contained 

 mature embryos in the dorsal brood-sac. Professor Ramsay 

 AVright mentions two species of each genus as occurring at Caiiso 

 {op. cit. 1907, p. 13). In the same year, what he claimed to be 

 the first American records of Evadne nordmanni Loven, and 

 Podon polyphemoides Leuckart, were made by L. W. Williams 

 (" List of the Rhode Island Copepoda, Phyllopoda, a,nd Ostracoda, 

 with new species of Copepoda." Special Paper, No. 30, 1907. 

 Reprinted from 37th Ann. Rep. of the Commissioners of Inland 

 Fisheries of Rhode Island, pp. 69-79, 3 plates). 



Of Dinoflagellates, Peridinium dive^-gens Ehrb. was sometimes 

 very abundant. In the peripheral part of the cytoplasm there 



