jQ. PORIFERA. I. 



'frr?T>>. 



^ 



him more than one species; at least the fact is that the two Haiiiacanf//a-s])&cies I have before me, 

 the present species and the following one, are entirely constant with regard to their spiculation; one 

 has always three forms of diancistra and toxa, the other always only one form of diancistra, and 

 rhaphides, but no toxa. To this constant difference in the spiculation is further, as appears from the 

 descriptions, added other constant characters. To judge by the forms of microsclera mentioned by 

 Topsent, it would appear that he has had three species, viz. the present one (all the specimens with 

 toxa), the following one (the specimen with rhaphides), and a species with sigmata. As has been 

 shown, we do not at present know with certainty, what H.JoJnisoiii is, and therefore I presume it will 

 be best by the determination to leave this species out of consideration. 



On the other hand there might be some possibility that Halichoudria falciila Bow. is identical 

 with the present .species, but this fact cannot be decided by Bower bank's description. Thus he 

 mentions and figures only one form of diancistra; as skeleton-spicule he figures a stylus of common 

 form, but in the description he uses the term fusiforrai-acuate . The description of the external form 

 and the surface agrees well with the present species. Finalh' the species is obtained at the Shetland 

 Islands, which locality is not very far from several of the stations, on which H. Bo'iverbanki is obtained. 

 The Hymedesmia Joliiiso)ii mentioned by Carter 1. c, seems, by being possessed of toxa, and also by 

 the description upon the whole, rather certainly to be identical with the present species. 



Locality: Station i, 62° 30' Lat. N., 8° 21' Long. W., depth 132 fathoms; station 9, 64° 18' Lat. N., 

 27° 00' Long. W., depth 295 fathoms; station 10, 64"" 24' Lat. N., 28° 50' Long. W., depth 788 fathoms; 

 station 27, 64° 54' Lat. N., 55° 10' Long. W., depth 393 fathoms; station 81, 61° 44' Lat. N., 27" 00' Long. W., 

 depth 485 fathoms; station 85, 63° 21' Lat. N., 25^ 21' Long. W., depth 170 fathoms; .station 89, 64'' 45' 

 Lat. N., 27" 20' Long. W., depth 310 fathoms; station 90, 64' 45' Lat. N., 29^06' Long. W., depth 568 fa- 

 thoms; station 94, 64"" 56' Lat. N., 36" 19' Long. W., depth 204 fathoms; station 97, 65° 28' Lat. N., 27° 39' 

 Long. W., depth 450 fathoms; station 98, 65' 38' Lat. N., 26" 27' Long. W., depth 138 fathoms; station 112, 

 67° 57' Lat. N., 6° 44' Long. W., depth 1267 fathoms (temperature -f- i"i C). Finally it has been taken 

 on 64° 42' Lat. N., 27° 43' Long. W., depth 426 fathoms (Wandel). All these stations are between ca. 62" 

 and 68° Lat. N., and are dispersed in the sea between the Faroe Islands and Iceland, to the south of 

 Iceland, the Denmark Strait, and the Davis Strait. The depth ranges between 132 and 1267 fathoms. 

 On some of the stations, especially station 89, the species has been taken in very large numbers. On 

 station 112 with the great depth of 1267 fathoms and the negative bottom temperature only a single 

 quite small specimen was taken. On the other hand the largest specimens are from the stations i 

 and 98 with depths of respectively 132 and 138 fathoms. 



Gcogr.distr. Carter I.e. mentions his Hyiiicdcsiuia Johiisoni from between Scotland and the 

 Faroe Islands and from Madeira. According to what is stated above, the species must also be sup- 

 posed to have been taken on the expedition of the Prince of Monaco 1886—88. 



2. H. implicans n. sp. 

 PI. V, Figs. 6-9, PI. XIX, Fig. I a— e. Figs. 2— 6. 

 1885. "^ Haiiiacautim papillata Vosmaer, Sponges of the ;,Villeni Barents , Bijdrag. tot de Dierk., 12*:'; Afl. 

 3die Oedeelt. 28, PI. I, fig. 15 a— b, PL V, figs. 82—86. 



