Bipinnaria. 



In Feb. 1896 I took l>ii>iiinaria at several places along the 

 west coast The small tire-armed sea-stars could distinctly be seen 

 on all, and the arrangement of the processes on the larva* makes 

 it likely that all must be classed among bipinnaria asterigera, 

 San. In a surface sample taken in 61 9.5' N. and 3 50.5' 

 K . Mar 12th, 1896, a little sea-star was found the appearance 

 of which corresponds well with the small ones on the bipinnaria 

 mentioned. It seems to have been made evident that '-. a$teri<i< m 

 is the larva of Inidia sargii, whose spawning time must consequently 

 be very irregular as Mr. M. SABS has observed tin- said larvae in 

 May. Messrs. KOBEN and DANIELSES in the months September 

 October, and I in February. 



Spadclla (sagitta) hamata. Mobius. 



This chsetognath I have taken many times, both in the fjords 

 near Bergen and in Lofoten, but never in shallow water. Mr. 

 MoBirs*) mentions it from the Korsfjord in depths of from 135 to 

 337 fathoms, while AURIVILLIUS, daring the Swedish Scagerrack 

 Expedition of 1893 94, notes it from 100 m. in water whose 

 saltness was 22.3135.05 %o, and temperature 2.85 17.3 C. 

 Mr. At'BiviLLirs**) gives the length at 18 mm. for specimens from 

 the Swedish Scagerrack coast. The largest ones I have till now 

 measured were 24 mm. (Feb. 23th, 1897; between Bare and Lii- 

 dingen, 0190 m.). Mr. STRODTMANN states that s. hamata may 

 reach the length of 3 4 cm., but such large individuals are pro- 

 bably only found in high arctic regions. I have the idea that s. 

 hamata at our coast is thriving best in water of 6 7 C., and 

 with a saltness of 34 35 /oo. In some places, as in the Ostnes- 

 fjord and at Sundero in Vesteraalen, I have observed chasiogiiata 

 also in the surface, but this has been another kind (.. bipunctata). 



Tomopteris septentrionalis, Stenstrup. 



In "Videnskabelige Meddelelser fra den Natuihistoriske For- 

 ening i Kjobenhavn r , 1849 50, p. IV, Mr. STENSTBUP states that 

 the Copenhagen Museum had received from dr. RINK a great num- 

 ber of specimens of this kind, in part taken a few miles off the 

 Norwegian coast, in part in the sea round the Orkneys and the 

 Faroe islands. Mr. STENSTRUP considered it different from the 

 form observed in the South Sea by ESCHHOLTZ (t. onisciformis). 

 In "Fflnfter Bericht der Kommission zur w. Unters. d. Deutsch. 

 Meere r . Mr. Monies (p 117) has mentioned a form, t. helgolandica, 

 Greef, which in all probability is synonymous with t. septentrionalis. 

 Besides in other places, the German Expedition has also observed 

 the form mentioned in the neighbourhood of Lindesnes. Mr. G. 

 0. SABS has informed me that he has often met with tomopteris 



*) Jahrabericht der Communion zur wiwentuchaftl. Untenuch. d. DeuUch. 

 X. II. Ill Jahrg., p. 158. 



**) DM Plankton des Baltinchen Meerei, p. 37 (Bihang t. Kgl. 8. Vet 

 Akad. HandL Band. 21, Stockholm 1896). 



both in the Kristiania-fjord and along the whole West-coast as far 

 as Lofoten. In the many plancton samples that I have taken 

 during the last two years, this form has only occurred a sinjile 

 time, namely Feb. 25th, 1897, in the Ofoten-fjord in a sample 

 from 250 m. Further, dr. AITKI.I.HK took a fine specimen in 

 the Bergen By-fjord in the summer 1894. It had a total length of 

 about 40 nun. 



Calanus finmarchieuf. Gunnerus. 



Mr. GIESBRECHT has noticed that this is probably the first 

 marine pelagic copepod that has been described. That honour 

 belongs to the Norwegian bishop JOHAN ERNST GTNNEBCS (1718 

 1773). The original name was monwului> fhimarchirus, and the 

 original description is found in "Det Kongelig Norske Videnskabs- 

 selskabs Skrifter". This copepod seems to occur in the plancton 

 at our coast at any time of the year, at least the females, the 

 males on the contrary being rarer. Mr. GIESBRECHT in his "Mono- 

 graphic" gives the following measures for the female: 

 At Naples 2.72.9 mm. 



- Gibraltar 3.0 



- Spitsbergen, the largest ones 4 4.5 



The grown-up males are stated to vary between 2.35 3.2 mm. 

 I have undertaken a number of measurements of both sexes. 

 Feb. 23th, 1897; between Baro and Lcidingen; 200 m. 

 9 3.7 mm. 

 d" 3.6 

 d" 3.6 



Feb. 24th, 1897; off the mouth of the Tjeldsund; 0200 m. 

 9 3.7 mm. 

 cT 3.3 

 CT3.2 

 July 1st, 1897; 15 geogr. miles north of Jan Mayn; m. 



9 5.0 mm. 



Feb. 14th, 1898; Herliifjord near Bergen; 0400 m. 

 9 3.0 mm. 

 cT 3.4 



From this will be seen that even in the deep of the fjords 

 near Bergen the male may reach the length of 3.4 mm., while in 

 the arctic sea the female can reach a length of 5 mm. The upper 

 limit of variation is thus somewhat extended. 



Calanus hyperbareus, Kroyer. 



9 



Apart from the difference of size, the female of c. hypcrborcits 

 is easily distinguished from c. ftnm. Q, the lateral corners of the 

 5th body-segment being pointed in the former, while they are 

 rounded off in the latter. The arrangement of teeth on the basal 

 joint in the fifth pair of feet (fig. 28) also gives a good mark of 

 distinction. The interval of variation is stated by GIESBRECHT to 

 be 6.9 9.6 mm. Having taken several specimens of the said form 

 both in Lofoten and in the Ofoten-fjord, I give here some measures. 



