64 THEEL, NORTHERN AND ARCTIC INVERTEBRATES. I. SIPUNCULIDS. 
in Hinloopen Strait, stones and mud, 36 fms. (Sp. Exp. "/, 1868), I sp. — Waygat 
Island in Hinloopen Strait, stones and mud, 30 fms. (Sp. Exp.), I sp. — King Charles” 
Land, 78” 50' n.—29?” 39' e., fine, blackish gray clay, 60—70 m. (Sp. Exp. '”/s 1898), I sp. 
Finmarken: Tromsö, low tide (Sp. Exp. '/s 1861), 20 sps. — Grötsund, clay, 
60 fms., 6 sps. — Ulfsfjord, 25 fms. (Sp. Exp.), 7 sps. — Hammerfest, Komagfjord, 
4 sps. (Mus. Chr.). — Tromsö and Kv&enangen (Mus. T.). 
Peninsula Kola: Kola Fjord, 140—148 fms. (Sand. Exp. ”/s 1877) 2 sps. — 
Semiostrowa, 60 fms. (Sand. Exp. '”/s 1877), 1 sp. — Ora Fjord (Sand. Exp. ”/s 1877) 1 sp. 
Novaya Zemlya: Möller Bay, 72”, 31 n.—52” 45 e., sand and stones, 5—20 
fms. (Yen. Exp. ”/, 1875), I sp. — Matotschkin Strait, mud and Lithothamnium, 
153 fms. (Yen. Exp. '/s 1876), 1 sp. — Kostin scharr, 4 sps. (Mus. Chr.). 
The body-wall of "Forma finmarchica"" is more firm and thick, and its reticulate 
structure is more conspicuous than in "Forma sibirica"". Besides, the glands of the 
skin posteriorly seem to be more crowded, which may possibly depend upon a higher 
state of contraction, its muscular layers being more powerful. In proportion to the 
size of the body the tentacles are often more numerous and slightly longer in this 
form than in the easterly one. In young individuals the number of them is small. 
Thus, a very young specimen from Clavering Island had only 8 tentacles. 
The subjoined table is intended to give an idea of the fluctuations of the 
tentacles of the westerly form. 
Number of the Length of the Diametre of 
»Forma Finmarchica» Localities 
tentacles. kody. the body. 
| | i | 
| 8 7,5 mm. 1 mm. | Clavering Island (Bast Greenland). | 
| | 18 | 15 mm. | 2,3 mm. | »> | 
34 | 20 mm. | 4 mm. | Finmarken (Mus. B-.) 
26 | 22 mm. | 4,5 mi. | Tromsö. 
44 | 40 mm. | 6,5 mm. | Bel Sound (Spitzb.) 
S7 47 mm. | 7 mm. | Tromsö. 
S3 | 50 mm. | 7,5 mm. Finmarken (Mus. B-). 
55 65 mm. | S mm. | Tromsö. 
74 70 mm. | 3 mim. | > 
97 i 70 mm. | 10 mm. » 
104 | 70 mm. | 10 mm. | » 
"Forma sibirica.”' 
Habitat: 
Siberia: North of Asia, without: definite locality (Vega Exp. 1878), 4 sps. — 
75” n.—113” 30' e., stones and clay, 15 fms. (Vega Exp. ”'/s 1878), 20 sps. — Konyam 
Bay in Bering Strait, sand, 15—16 fms. (Vega Exp. ”'/; 1879), about 20 sps. 
The specimens, which were obtained by dredging at a station situated in 75” n. 
-=113” 30' e., present in alcohol a yellowish white colour, while those from the Bering- 
Strait are of a grayish violet colour; this difference may possibly depend upon dif- 
