Marine Plankton from the East-Greenland Sea. 329' 



and Distephaniis speculum. From the transition to the inner group 

 we have a single sample (No. 17 in the Table), which mainly con- 

 sists of Melosira hyperborea (with resting spores) and Calanus fmmar- 

 chicus; the very low temperature ( — 1"2°) implies special conditions 

 in the water, e. g. that the sample might have come from the immed- 

 iate vicinity of an ice-floe. 



The inner group (5 samples) come from water with a temperature 

 of ca. 0° and a salinity of 306 — Sl^^/oo and the samples were taken 

 from ca. 18° W. L. (ca. 90 miles from land) in towards the coast (Ger- 

 mania Land and Koldewey Island). The principal species are Chaet. 

 boréale, Ch. decipiens, which in small quantities were also found in 

 the samples from the outer group, and Oithona similis; Rhizosolenia 

 styliformis replaces the other two Rhizosolenia species. Coscinodiscus 

 subbuliens and Apodinium Chaetoceratis only occur in the samples from 

 near the coast. In a couple of the samples Calanus fmmarchicus was 

 present in large numbers. With regard to the Peridinians, Ceratium 

 arcticum was found in small quantity and usually only as empty 

 shells in all the samples (also of the outer group), whilst the other 

 species had practically disappeared. 



b. July— August 1908. (Table III). 

 V/e have examined 28 samples taken on the return voyage du- 

 ring the period from July 21st to August 3rd in almost the same 

 region as the samples from 1906. 



The samples can be divided naturally into three groups: 

 The inner group (15 samples) goes from the coast to ca. 14° W. L.. 

 The salinity determinations are few; they vary between 28'1 and 

 31 7 "/oo and the temperature on the surface lies between 0° and — 4° C. 

 The samples are somewhat rich in species, the most prominent being 

 the following diatoms: Chaetoceras decipiens, Ch. boréale and Coscino- 

 discus subbuliens, and common to all is the small quantity of Peri- 

 dinians: Per. conicoides, P. curvipes and Ceratium arcticum being the 

 near most characteristic. Three samples taken west of Germania Land 

 (Nos. 1276, 1279, 1289) in water with 3 — 4° temperature (and presu- 

 mably low salinity) are wanting in, among others, Chaet. Wighaiui 

 and Fragilaria oceanica, which are found otherwise in larger or 

 smaller number in most samples. Chaet. sociale appears lirst further 

 away from land (from No. 1290), but is then constantly present and 

 usually in quantity. Calanus finmarchicus and Thalassiosira gravida 

 (to a smaller extent) chiefly keep on the other hand to the samples 

 from nearer land. The two northernmost (ca. 78° N. L.) samples 

 (Nos. 1301, 1303) are remarkable for a large quantity of Melosira 



