136 G 



Canadian Arctic E.vimlHi<m, 1913-1918 



England in 18 to 264 fathoms. Off Watch Hill, K.I., in 18 fathoms, young. 

 It was also brought from the fishing Banks oft Nova Scotia by the Gloucester, 

 Mass., fishermen. It ><< nis to be a common species in deep water, judging by 

 the number of empty tubes brought up in the dredges. It also occurs in the, 

 Gulf of St. Lawrence (Whiteave's coll.) 



Young specimens from 25 to 35 mm. long are often found off the New 

 England coast in moderate depths. 



One of these, about 33 mm. long, is figured (X2) on pi. XXII, fig. 3, from 

 life. This had 22 slender marginal tentacles; the labial tentacles were relatively 

 shorter than in the adult. The body wall was translucent, so that the larin T 

 mesenteries could be seen by translucency. The aboral end was mobile and 

 changeable in form, often inflated, as in the figure. In colour it was similar to 

 some of the adults, but the body was pale greenish brown. 



When the marginal tentacles of such specimens are broken off, as often 

 happens in a dredge containing stones, shells, etc., the young Cerianthus, with 

 its margin contracted, and showing the labial tentacles, very much resembles 

 an Ilyanthus, and may easily be mistaken for that genus when superficially 

 examined (fig. 19). When more closely examined the thick margin shows its 

 real nature. Of course an examination of the interior by sections shows the 

 difference at once. 



A small specimen, about 75 mm. long and 6 mm. in diameter, taken off 

 W^atch Hill, R.I., July 31, 1874, in 18 fathoms, had the body pale purplish brown 

 anteriorly, greenish brown to olive posteriorly; just below the outer bases of the 

 tentacles was a ring of orange-brown; outer tentacles flake-white at base; inner 

 marginal tentacles had a spot of purple on each side and on the front of the 

 base; labial tentacles were purplish, with some flake- white at the tips. Some 

 of the marginal tentacles had a white stripe at about the middle, on each side. 



Arachnactis brachiolata A. AGASSIZ. 



Young larvae of Cerianthus. 

 Text Figures 21, a, b, b 1 , 22. Plate XXII; Fig. 4. 



Two stages of development of this interesting larval form were taken Oct. 

 4, 1913, at Station 27 1, u, Collinson point, Alaska, swimming under ice in about 

 1 fathom of water. 



According to Mr. F. Johansen's notes, these larvae were floating with the 

 rounded basal end upward, and the four larger tentacles downward. The 

 tentacles were slightly ourved at the tips, and spread out in a quadrate. The 

 tips of these outer tentacles were orange-brown, elsewhere the larvae were pale 

 yellowish brown, the ends being darker. The length was about 4-5 mm. Two 

 pairs of inner or oral tentacles were observed. 



The three specimens received by me represent two diverse stages of develop- 

 ment. (See Text Figures 21, a, b). The younger stage (a) has two pairs of 

 outer tentacles well-developed, but somewhat unequal, with rudiments of one 

 of the third pair. It has two rudimentary oral tentacles and a large, slightly 

 emarginate, protruding oral lobe or lip. The body is short and thick, evenly 

 rounded posteriorly. One pair of mesenteries is conspicuous. The other 

 specimen (b, b 1 ) is considerably older. It has the third pair (i, i, i) of tentacles 

 pretty well developed and crossed by a whitish band on the inner surface. There 

 are rudiments of four oral tentacles (two pairs) unequally developed. Eight 

 unequal pairs of mesenteries can be seen by translucency; only one pair reaching 

 nearly to the end of the body. 



