PORIFERA. I. 89 



Spiciila: a. Mcgasrlrrn are lon<;-, rather slender styli; more or less cnr\-ed, almost always nearest 

 to the head end; the other end is evenh' and long tapering, the ontermost point itself ma\' be shorter 

 or longer. In some of the shorter styli the cnrve is fonnd quite close to the headend. The length 

 is somewhat \arying, and is between i-8 — 0-3™'"; the shorter ones have all a cnrve close to the head- 

 end, but are otherwise straight. The most frequent length seems to l)e 17 — i-::;"'"'; the thickness at 

 the upper end is 003—0023""". Finer st\li occur, but onl\- in very small numbers. Irregular forms 

 with the thin end rounded ma\- also be found singly. The styli, as shown above, divide into two 

 groups, which are, however, not quite sharply separated: the txpical long, more evenh- curved styli, 

 and the shorter ones with a somewhat sharper cnrve close to the upper end. The length of the 

 former may be given to be between 17 — o-8""", of the latter between 07 — 0-3'"'". 



Besides the mentioned st\ li that form the fibres of the skeleton, some other styli occur, which 

 are short, of an average length of o-26""", and irregularh' curved or sinuous to a higher or lower 

 degree. These styli, however, occur in a particular way, being onK- found in the part of the sponge 

 that is attached to the substratum, where the\- form a thin layer. 



b. Microsclera : i. Sigmata of two sizes; the larger ones have a regularly curved .shaft, and the 

 recurved ends form a hook that is almost rectangular; generally they are not contort, or only contort 

 to a small degree. They are somewhat varying in size, the length being o-i'""' down to 0-04'""', and the 

 thickness proportionately 0-0047— 0-002""" ; '^^ey are found both singly and in bundles of different sizes. 

 The small sigmata have a form resembling that of the large ones; their length varies from 0-031— 0-019""", 

 the thickness is ca. o-ooi""'". Neither are these sigmata contort. The\- are more numerous than the 

 large, but do not appear to occur in bundles. 2. Rhaphides; these have a length of 0-176-0-19'""', and 

 an average thickness of o-ooi"""; the>- are very long and finely tapering to both ends. vSmgle rhaphides 

 are found scattered, but b\- far the greatest part occur in loose bundles. 3. Connnata; small, comma- 

 shaped, verv fine st>-h of a length of ca. 0-02'""'; at the upper end the>- have a thickness of ca. 0-0007'"'", 

 they are evenh- curved, and taper to a long, exceedingly fine point. As seen from this description 

 the>- are very small, and consequently they are easily overlooked. In this sponge they are only found 

 in ver}- small numbers, which is, perhaps, due to the fact that we have onh- the lower part of the 

 sponge, and therefore I have not been able to observe, whether the>- occur in any particular -way in 

 the sponge. Levinsen I.e. does not mention these spicules, but by an examination of his original 

 specimen I have found them, although also only in small numbers'). Besides in the dermal membrane 

 sigmata and rhaphides are also fonnd in the other tissue. 



As I have had occasion to make a comparison with the original specimen of Levinsen, I 

 have been able with certaint> to identif\- the species. The spicules agree ^-er\- well, onl\- are the rha- 

 phides in my specimen upon the whole somewhat shorter, which is, howe\-er, .scarcely of any import- 

 ance. With regard to the quoting of Lam be I cannot be so certain, as here some difference is 



I) These .silicious bodies for which 1 propose the name of couimata, on account of their form, have only been men- 

 tioned once, viz. by Fristedt (Kgl. Sv. Vet. Akad. Handl. Bd. 21, No. 6, 29, Tab. II. Fig. 10 i) in a Desmacelta-^^^aes, which he 

 calls D. Pcjchii Bow. var. stellifera. As I have found them, however, in all four species before me, and as on account of their 

 smallness and inconspicuous form, they are easily overlooked, I think mj'self justified in taking it for granted that they have 

 been overlooked by the authors in the species belonging here. Therefore by the identification I have not taken the fact into 

 consideration that they have not been mentioned in two of the following species. 



The Ingolf-Eipedition. VI. i. '^ 



