9 9 



3 



Spicules. Parenchymal diacts (Figs. 5, 6), 1360 to 3100 X 5 to 

 10 ^t, smooth^ but with roughened rounded ends, and occasion'- 

 ally with two or four knobs with aborted axial canals; triacts and 

 tetracts of the same character as the diacts, occurring rarely. 

 Large diacts of stalk (Fig. 7) 10 mm. X -128 mm. 



Parenchymal hexacts of various sizes, the largest with conical 

 rays each 620 /. in length, and with centrum 32 /i in diameter. 



Autodermal pentacts with rough truncate rays each 285 /« in 

 length, and without a distal knob. The surface pentacts of the 

 stalk (Fig. 9) with long smooth tapering tangentials each 220 to 

 520 /< in length, the vertical ray being sharp-pointed and from 

 50-100 /( in length. 



Autogastral pentacts (Fig. 8) mostly resembling autoder- 

 mal pentacts, but some ia the floor of the cup having smooth 

 tapering rays like those of the stalk pentacts. 



Hypogastral hexacts (Fig. 10) and the slightly smaller hexacts 

 of the stalk canals regular, with roughened blunt-pointed rays 40- 

 iio /< in length, with a small centrum. 



Intermedia, oxyhexasters (Fig. ii) 62 /i in diameter, the almost 

 aborted primary rays giving rise to two (usually) or three secon- 

 dary rays with roughened surface. 



The species is named after Professor E. Ray Lankester. 



Locality. — Three specimens were obtained by shrimp trawl 

 from a depth oif 250 to 300 fathoms^ East London N-W. ^ N. 

 distant 18 miles. Bottom — broken shells, hard ground- 



Of the three specimens two are dried and the third and 

 smallest is preserved in formalin- The largest (A) is 31 cm. in 

 height, the diameter at the rim being 22 cm., and the depth of the 

 cup II cm.; the length of the stem is 22 cm., the diameter below 

 being 3X6 cm-, and at the upper end 4X3 cm. ; the system of- 

 cp.nals in the centre of the stem occupies, near the lower end, 'a 



diameter of 0.6 c m. 



The dimensions in centimetres of specimens B and C are as 

 follows : — 



B- C. 



Height 20 12 



Diameter of rim .... 15 7 



Length of stalk 10 6 



Specimen B has a double stem, a long slit-like fenestra extend- 

 ing neariy the whole length- Specimen A was the best preserved, 

 but even here, the dermal membrane and to a still greater extent 

 the autogastral laver had almost disappeared. 



Trawls and dredges are not quite suitable implements for 

 obtaining delicate Hexactinellid Sponges, much better success 

 being obtained by the " long-line " method advocated by Ijimia, 

 [4], and [5], p. 16. . .' 



The specimens appear to have been torn up from their pomts 

 of attachment: the lower ends are clear of any foreign matter. 



