g 2 PORIFERA. II. 



Q.Qjgmm an( j 'io mm , and the thickness is proportionately 0-005 — o-oo6 mm . 3. The small sigmata are 

 of a peculiar form not mentioned by Sars, about as the form known from sigmata in some of the 

 Asiestoflluma-sipecies, bnt here much more sharply marked. Either end of the sigma from the middle 

 and to the point of the recurved part is highly compressed and inwardly sharpened in an edge-like 

 manner. The sigma is contort, and almost always rather exactly one fourth of a turning. The length 

 is 0-040 — o - 042 mm and the thickness in the middle ca. o-ooi5 mm . The small sigmata, as stated by Sars, 

 occur in the points of the branches in somewhat greater numbers, but besides they occur also in 

 other places of the tissue, but only in very small numbers. The large sigma is stated by Sars to 

 occur scattered in the tissue, and in greater numbers in the points of the branches; this statement I 

 have not found corroborated, but have found this sigma occurring equally frequently everywhere in 

 the tissue, but not especially copiously. The ancorse are present in great abundance, partly throughout 

 the tissue, and especially in the skin or the outer layer; thus they are seen very abundantly in the 

 thin layer of tissue on the branchlets. 



Embryos. Embryos were found scattered in the tissue in rather great numbers. They are 

 globular and reach a size of ca. o , 35 ,n,n in diameter. They contain no spicules. According to Sars 

 the embryos seem to be developed in the ends of the branches; this fact I did not find corroborated 

 by my material; later, at all events, they are found everywhere in the tissue in great numbers, as has 

 also been observed by Sars. They were also found in the small, unbranched specimens. 



Remarks: A sure determination of this species is no easy thing, as it is very closely allied to 

 the succeeding ones, and has also constantly been confounded with them. I was long in doubt whether 

 the present species and the following one were specifically different; there are, however, constant char- 

 acters, especially in the size of the spicules, and it was found, moreover, that C. abyssicola occurs only 

 on bottom with positive temperature, while the following species is a native of the cold area. I have not 

 seen Sars's type specimen, but a specimen sent by Dr. Nordgaard, obtained on Sars's old locality, 

 Skraaven, agreed exactly as well with the description by Sars as with my specimens. The species 

 mentioned by Wyville Thomson in The Depths of the Sea , and by Carter in his work on the 

 v Porcupine --sponges as C. abyssicola belong surely, as already mentioned, to some of the succeeding 

 species. With regard to the C. abyssicola mentioned by Armauer Hansen in The Norwegian North- 

 Atlantic Exp. XIII, the fact is most probably that he has not had this species before him at all; all 

 the figures of the exterior show on the contrary that he has had the four following species, gelida, 

 tenuisigma, corticocancellata, and oxeata. and those of the spicula-figures that can be interpreted at all 

 show also that the question is not of abyssicola. I have examined two of his specimens which 

 belonged respectively to the two following species, gelida and oxeata. All the enumerated localities 

 are also seen to be situated in the cold area, with only one exception, and this one is found at the 

 very border of this area. Of the C. abyssicola mentioned by Fristedt (Vega-Exp. vetensk. Iaktt. IV, 

 455) I have examined one specimen which proved to be C. oxeata. The specimen mentioned by 

 Lam be I.e., on the other hand, is no doubt C. abyssicola, as is obvious from the description; when 

 Lam be says that the ancorre seem only to have three teeth in either end, this is no doubt only 

 owing to the fact that he has not seen them from the end. Finally it must be noted that the two 

 forms mentioned by Ridley and Dendy, C. abyssicola var. rcctangularis with styli up to 2 mm long, 



