COPEPODA 



69 



189S. Clausocalanus arcuiforniis Dana Giesbrecht & Schmeil, 



1899. 

 1900. 

 1901. 

 1903. 



1903. 

 1904. 

 1905. 

 i9°5- 



p. 27. 



1906. 



Brady, p. 32. 



1908. 



Wheeler, p. 171, fig. 9. 



1908. 



Cleve, p. 5. 



1909. 



J. C. Thompson & A. 



1909. 



Scott, p. 243. 



1910. 



Cleve, p. 359. 



1 9 10. 



Cleve, p. 1 88. 



1911. 



Wolfenden, p. 999. 



1912. 



Esterly, p. 142, fig. 13. 



1912. 



1905. Clausocalanus arcuiforniis Dana G. O. Sars, p. 3. 



Pearson, p. 9. 

 v. Bremen, p. 23, fig. 20. 

 Farran, p. 28. 

 Pesta, p. 22. 

 A. Scott, p. 32. 

 Steuer, p. 22. 

 Farran, pp. 91—92. 

 Wolfenden, p. 203. 

 Pesta, pp. 20-21. 

 Sewell, p. 360. 



Description. Between the specimens described by Giesbrecht and my specimens scarcely any 

 differences were found. As far as the oral surroundings are concerned they scarcely show features of 

 greater interest. Just behind the rostrum a low epistoma bearing a few rather short and strong 

 bristles (fig. 9 a) is found. In the middle of the labmm proper a rather prominent, narrow and hairy 

 process is found, on each side of which a group of rather short setae is seen. Posteriorly the labrum 

 is on each side produced into a hairy wing-like rounded expansion. The oral surface of the labrum 

 (PI. I fig. 9 c) possesses on each side 3 — 4 longitudinal rows of short setae, and between these 3 trans- 

 verse groups, of which the posterior is the most developed. 



The lamina labialis has three subdivisions. Orally and anteriorly two interiorly convex series 

 of hairs are observed on each side. The arrangement of the hairs behind the lamina labialis did not 

 show features of greater interest (PI. I, fig. 9d). 



Occurrence. This species seems to be extremely rare within the area explored by the Ingolf 

 Expedition; I have only examined 11 full-grown females and a single young one, which were taken 

 2 V 4 1889 59 Lat. North and 17° Long. West. 



Distribution. The species has previously been found on the west coast of Ireland r . In the 

 Mediterranean it has been recorded by several authors. In the northern as well as in the southern 

 parts of the Atlantic Seas it has been captured by the Monaco and the German Antarctic Expeditions. 

 On the west coast of South America it has been found as far south as 53 S. By Wolfenden it is 

 recorded from the Maladive Islands and from the Antarctic Seas as far south as Lat. 84°oi, and by 

 Brady from New Zealand (at the surface). In the Pacific Ocean it has been found between 20 Lat. 

 North and 26° Lat. South. Vertical range from the surface to 4000 met. Cleve has found the species 

 in the Arabian Sea (Temperat. between 24-8° and 267 C. and salinity between 36-20 and 3577 %o), 

 the Indian Ocean (7— 4 Lat. North T 277 — 29-35° C, Sal. 30-84 -34-38 % ) and in the Malay Archipe- 

 lago (T. 25-3° — 28-30° C. Sal. 32-22— 33-8o°/oo). According to Scott (1909 p. 32) it is moderately common 

 over the whole area investigated by the Siboga Expedition. 



13. Spinocalanus abyssalis Giesbrecht. 

 (Plate I figs. 10a — b; textfigs. 15 a — e). 



1888. Spinocalanus abyssalis n. sp. Giesbrecht. 

 1892. — — Giesbr. Giesbrecht, 1892 pp. 209 



— 213, taf. 13 and 36. 



1900. Spinocalanus longicornis n. sp. (9) G. O. Sars, pp. 75 — 78, 



pi. XXII. 



1 According to Farran (1910 p. 92) "it is occasionally carried by currents into the mouths of the English Channel 

 and the British Channel, but has not yet been recorded from the west or north coast of Scotland". (Salinity 35 4°/ooj- 



