l2 . PORIFERA. III. 



sometimes the legs are curved slightly outwards and then a little more divergent below; these for- 

 cipes have thus a shape about as the large forcipes in Forccpia Topsentii (The Danish Ingolf Exp. VI, 

 2, 1905, PI. XIX, fig. 4 d). The forcipes are grittily or rugosely spinulous, and the legs are irregularly 

 rounded or somewhat pointed at the apex, without any knob; they are smooth on the inside of the 

 upper curve. The length of the forceps is 0-024 — °'°34 n,n \ an d the thickness of the rod is above in 

 the curve 00035 — 0-0056 mm . In single cases the forceps has the legs extraordinarily divergent, so that 

 the angle is obtuse; this feature is thus parallel to what is likewise the case with the forceps in 

 Forccpia Topsentii, (1. c. fig. 4 e). 4. The small forceps has the legs parallel or slightly divergent, 

 and one leg is longer than the other; this longer leg is curved slightly inwards; the legs terminate 

 with a little knob. This forceps recalls thus the forceps in Forccpia Thielei and F. groenlandica (The 

 Danish Ingolf Exp. VI, 2, PI. XIX, fig. 5 d, PL XX, fig. 3d.); it is inconspicuously spinulous. This 

 forceps is very small, the total length from the curvature to the end of the long leg is 0-014— o-oi8 mm , 

 and the thickness above in the curve is about 0-0007 mm . Of the microsclera the chelae and sigmata 

 are numerous, they are seen especially in the dermal membrane, but occur also through the whole 

 sponge; the forcipes are not numerous but of somewhat rare occurrence, and they are not seen in the 

 dermal membrane; otherwise it must be remarked, that the small forceps is difficult to detect on 

 account of its very small size, and it is therefore very liable to be overlooked. 



This species is evidently nearly related to L. forcipula var. brunnca Tops, which I take to be 

 certainly a distinct species, not specifically identical with forcipula; but the present species differs 

 from brunnca with regard to the size of both megasclera and microsclera; thus Top sent gives the 

 size of the chela to 0-033 mm , an( ^ ne does not speak of variation in size; the large forceps in brunnca 

 has also a different shape, the legs being more divergent in their outer part; finally the acanthostyli 

 in assimilis have no specially strong spines at the base and have not the spines on the shaft reclined, 

 both these features being found in brunnca. I may also note, that in assimilis I have found no "cel- 

 lules spheruleuses" which are mentioned by Topsent for brunnea. Tops en t mentions, besides the 

 larger forcipes, some small ones of a length of 0-013 mm and very thin, but he does not describe them 

 more particularly; he thinks that they "representent soit la form jeune soit une etat athrophique de 

 cette sort de microscleres". Developmental stages they cannot be, according to what we know about the 

 development of the spicules, the growth taking place only by apposition; there is on the other hand 

 also no reason to believe them to be atrophied forms. It is no doubt a special, small forceps, so that 

 brunnca, like arcuata and the present species, has also two forms of forcipes, large and small. 



Locality: Station 46, West of the Faroe Islands, 6i°32'Lat.N., n°36'L,ong.W., depth 730 fathoms. 

 One specimen. 



't!>3«®i <J" ~ 



