ATLANT. DEEP-SEA EXPED. 1910. VOL III]. 



SPONGIA. 



11 



From station 10 there are only two small fragments, 

 one a piece of the body-wall, the other apparently a por- 

 tion of a central conus— both impossible to recognize. 



From station 35 was obtained a twisted basal tuft, 

 33 cm. long aad 0.5 cm. in diameter, with a fragment 

 of the body, 13 cm. long, adhering to its proximal pro- 

 longation. The basal tuft bears a single Palythoa. The 

 consistency of the body is very loose. Its spiculation 

 comes closest to that of H. lusitanicum Barb, du Bocage; 

 but it is doubtful whether it may be identified with this 

 species, especially on account of the pinnules, which in 

 form and size exhibit more likeness with those in H. 

 thomsoni Marsh; the distal ray of the great pinnules being 

 0.77 mm. long and the basal rays 0.09 mm. long; in the 

 small ones the distal ray is 0.26- -0.38 mm. long; the 

 basal rays vary much both absolutely and relatively, often 

 they are as long as the distal ray. 



The two specimens from station 53 are also in a bad 

 condition, the one consisting only of a hollow, 5 cm. long 

 fragment— most probably a compartment — attached to a 

 firm basal tuft 11 cm. long, which projects into the body 

 for about 3 cm.; the other specimen has a basal tuft 10 

 cm. long, the proximal prolongation of which projects as 

 a rigid conus into the middle of the body to a night of 

 1.2 cm. above the margin and apparently dividing the 

 body into four compartments of which only the one is 

 left. As the body-wall of the three compartments has 

 been destroyed, the central conus thus lies quite free. The 

 spiculation exhibits most likeness with that of H. lusita- 

 nicum. Thus we find the characteristic smooth micro-oxy- 

 hexacts, straight and bent, with rays 0.074 mm. long. 

 The pinnules— though the distal ray is shorter and the 

 basal rays seldom blunt as in H. lusitanicum — decidedly 

 resemble as regards their bushy appearance, the pinnules 

 of this species. As to the three kinds of amphidiscs they 

 too agree tolerably well in respect of form, but the 

 mesamphidiscs (0.05 mm.) and macramphidiscs (0.17 mm.), 

 are smaller — thus approximating in size to those of H. 

 thomsoni. The rest of the spiculation consists of diacts 

 variable in size and thickness, straight or curved, pointed 

 at both ends, and of middle sized oxyhexacts and pen- 

 tacts with their rays running into a marked point. In 

 the basal tuft there are strong spicules with a variable 

 number of cylindrical rays with rounded rough ends (like 

 those figured 26 pi. XXVIII, fig. 12). 



The identification of H. lusitanicum is on the whole 

 difficult imperfectly known as it is— erected by Barb, du 

 Bocage for a basal tuft of a sponge found at great 

 depths off Portugal. Had it not been for the amplification 

 of the diagnosis by Schulze based upon a damaged spe- 

 cimen labelled as a gift from du Bocage in the British 

 museum, it would have been impossible to recognize it. 



The specimens recorded by the "Gaudan" in the Gulf of 

 Gascogny, 1710 m., are only "lambeaux isoles, avec une 

 touffe de spies fixatrices couverte de Palythoa", and those 

 obtained by the "Valdivia" (30) south-west of Cape Bojador, 

 2500 m., are also only fragments, of which the author 

 remarks „vielleicht handelt es sich urn H. lusitanicum 

 Barb, du Boc. oder H. kentil Schmith." 



The only specimens of Hyalonema in a condition to 

 be recognized with any certainty are those from station 

 23, which I think must be referred to H. infundibulum 

 Topsent. 



The "Mihael Sars" specimens were found at the 

 following localities: 



Locality 



Depth & 

 bottom 



Number of specimens 



Spanish Bay: 



35" 32' N, 7" 7' W 1215 m. 



35" 34' N., 7" 35' W | 1615 m. 



Between Gran Canaria and I 



Cape Bojador: 

 28" 8' N„ 13" B. 5' W 1365 m. 



Unkown locality 



2 maceretcd specimens. 

 20 — 30 specim. (denuded). 



2 specimens. 

 11 dried specimens. 



Hyalonema infundibulum Topsent. 



(PI. I. fig. 8). 



Vide litter: 34, p. 28, 37, p. 277, 41, p. 32. 



St. 23. 2 specimens and 1 fragment. 



This form was first obtained by the "Hirondelle" 

 (1888) off Flores (Azores) at a depth of 1372 m. (bottom: 

 sable vaseux et coquilles brisees), and identified by Top- 

 sent as Hyalonema thomsoni Marsh 34. Later, after 

 having found in the material from the "Gaudan "-Expe- 

 dition (37), at a depth of 1710 m., "un echantillon 

 d'Hyalonema semblable a celui de I'Hirondelle'" he thinks 

 "maintenant avoir affaire a une espece voisine de/Y. Thom- 

 soni par la spiculation, mais nettement distincte par ses 

 caracteres exterieurs" — and he erects the species H. infun- 

 dibulum Tops. 



I believe that the specimens from the "Michael Sars" 

 station 23 (in the Spanish Bay) are to be identified with 

 this species. As to the exterior they agree very well 

 with fig. 12, pi. Ill (op. cit.), and according to the descrip- 

 tion (p. 278 op. cit.) they have a cylindroconical form, 

 the superior part of which, as the diagnosis runs "s'enfonce 

 en un entonnoir largement evase, dont la paroi, tapissee 

 d'une fine membrane criblee partout adherente aux tissus 

 sous-jacents, se perce de quatre grandes fentes allongees 

 et irregulieres, qui rayonnent autour d'un axe creux, et 

 aussi d'un plus grand nombre d'orifices plus petits et 

 inegaux. situes plus en dehors et disperses." 



