30 E. KIEKPATRICK. 



ends, each scoop having four or five denticles. One example has three sharp prongs 

 at one end and the spathulate prolongation at the other. 



The species is represented by numerous small, for the most part fragmentary, 

 slender cylindrical pieces. Many of the fragments came from the same locality as the 

 specimens of /. radiatus and were mixed up with them. Generally it was easy to 

 separate the two by the colour, that of I. radiatus usually being of a much darker 

 brown ; but in one or two instances the specimens of the new species were also dark 

 coloured. Several of the fragments are branched. The specimen figured (XXI. 5) is 

 4 cm. long and 5 mm. in diameter. The oscules are provided with a ring of radiating 

 amphityles, whereas /. radiatus is devoid of such structure. A glance at the spicules 

 at once enables one to distinguish the two species. The ectosomal amphityles of 

 /. radiatus have well-marked knobs spined all over, and not merely at the ends. The 

 choanosomal spicules of /. spatulatus are apparently modified acanthostyles, smooth 

 along the shaft, but with the spines at the rounded end gathered into one large 

 spine situated on the summit, thus giving it a tornote aspect. In one instance, the 

 single spine is represented by a little tuft of the spines. The axial canal terminates 

 some distance below the base of the spine. 



Several spherical embryos 268 m in diameter were present in one fragment, but 

 there were no special spicules in them. 



Since writing the above description, accounts of two new species of lophon from 

 the Antarctic have been published by Topsent (31. pp. 4-6), viz. /. unicornis and 

 /. pluricornis. The two new species described in the present Eeport and Topsent's 

 two species all possess the curious modified acanthostyles. I. unicornis Topsent, has no 

 bipocilla, and /. pluricornis has bipocilla apparently with pocillate ends ; the ' Dis- 

 covery ' species have spathulate bipocilla with crenulated ends ; and further, there are 

 diff"erences, viz., in the shape of the body, the arrangement of the skeleton, and the 

 character of the ectosomal spicules, which lead me to regard the ' Discovery ' specimens 

 as belonging to distinct species. A differential diagnosis of the four Antarctic 

 species with modified acanthostyles is given at the end of the description of the 

 next species. 



Fragments were dredged at No. 11 hole, 28 fms.; at No. 12 hole, 25-30 fms., and 

 off" Coulman Island, 100 fms. 



lOPHON FLABELLO-DIGITATUS. 



(Plate XXL, figs. 6, 6a-c, Plate XXV., fig. 6a-f, and Plate XXVL, fig. la-c\) 

 1907. lophon flaMlo-digitatus Kirkpatrick (10a. p. 277). 



Sponge forming a large palmato-digitate or digitate growth in one plane ; branches 

 compressed, usually with oscules along one edge. Surface finely verruculate ; with 

 elongated pore areas supported by fan-like wisps of ectosomal spicules. 



Colour dark brown ; consistence soft, the sponge being readily broken. 



