94 THE VOYAGE OF H.M.S. CHALLENGER. 



the hypogastralia, but here and there even beneath the gastral membrane, I am still 

 inclined to believe that here too they have been inserted on the tips of the hypogastral 

 spicules. 



Subfamily 3. T^geein^, F. E. Schulze (Pis. VII.-XL). 



The wall of the saccular or tubular body is perforated by apertures of various 

 sizes, irregular in shape and arrangement. The lattice-like trabeculse of the skeleton 

 form, for the most part an u-regular network of partially cemented principal spicules. 

 The outer end of the distal ray of each dagger-shaped hypodermal hexaster bears 

 a floricome. 



Genus 1. Tiegeria, u. gen. 



Tsegeria pulchra, n. sp. (PI. VII.; PL VIII.; PI. XL figs. 1-3). 



In the neighbourhood of the Fiji Island, Kandavu (Station 174c, Lit. 19° 7' 50" S., 

 long. 178° 19' 35" E.), the trawl brought up, from a depth of 610 fathoms, on a bottom 

 of coral mud, an elegant Euplectellid, which is figured on PL VIL, after the restoration 

 made by Wyville Thomson from a somewhat damaged specimen. 



The thin-walled saccular body, which expands somewhat above the middle to a 

 maximum diameter of 6'5 cm., exhibits a circular section, and has a length of 20 cm. 

 Near the lower blind sack-like end there is a compact, tangled, somewhat lateral, basal 

 prolongation which grows on the firm substratum. The upper extremity bears a circular 

 opening, 3 cm. in diameter, which is surrounded by a somewhat firm margin, and 

 overarched by a beautiful corona of long, curved, siliceous spicules which bend towards 

 the centre. The lateral wall of the body is only from 2 to 3 mm. in thickness, 

 and is penetrated by numerous irregularly scattered, approximately circular, tolerably 

 large parietal apertures, varying from 3 to 4 mm. in diameter. These gaps are disposed 

 at intervals of from 1 to 2 cm. in the median portion of the sponge, but are, above and 

 below, somewhat more widely apart. Between these larger orifices, smaller round pores 

 here and there occur, varying from 1 to 2 mm. in diameter. The numerous, light, 

 roundish spots, however, which may be observed in the spirit specimen, and also in the 

 figure on PL VIL, occurring on the external surface between the above noted apertures, 

 are neither holes nor pits from the outside, but represent pit-like hoUowings on the inner 

 surface which do indeed in many cases become, at a later period, artificially opened and 

 converted into canals which pass completely through the wall. 



The larger beams of the supporting skeletal framework, together with the delicate 

 comitalia which surround them, are for the most part fused, by cementing matter 



