OALCAEEA. 27 



straight in facial view, but often slightly bent in side view at a point a 

 short distance from the junction with the paired rays. This bend is 

 connected with the close manner in which pairs of these spicules lie 

 together. Paired rays bent slightly downwards, nearly equal in length, 

 sharply pointed, 70 m to 110 /a long X'Sjn to 5 /x, thick. Oral anglS 140° 

 to 150°. Folding considerable, angle of fold 115° to 125°. Apical ray 

 thin, 50)u, to 65//- X SjH, considerably set over out of line with the basal 

 ray. Angle between apical and basal ray about 170°. 



Oscular spicules. The fringe consists of : — 



{i) Hastate oxea, nearly straight, 240 ju, to 700 /a long x 5 /a to 8 jn thick. 

 The edge consists of : — 



(k) Small quadriradiates. Basal ray straight, uniformly tapering to a sharp 

 point, 110 ju, to 170 ju. long x 5 /u, to 8 /a thick. Paired rays equal, 

 considerably curved downwards, sharply pointed, 60 /* to 100 /x long X 8/u 

 thick. Oral angle about 160°. 



Hypodictyon. 



Chiphorids in which the radial chambers with freely projecting distal cones are 

 linked so as to form a reticulated pattern round the large intercanals. The tubar 

 skeleton is articulate, the first joint being wholly or partially formed of chiactines. 



This new genus in the family Chiphoridae corresponds to the genus Tenthrenodes in 

 the family Sycettidse. 



There is only one species in this genus. 



Hypodictyon longstaffi. 



(Plate XXVIL, Fig. 10, and Plates XXXIII. and XXXIV., Figs. 81-97.) 



There are four specimens of this new species in the collection. All are in the form 

 of longish tubes more or less bent, stouter in the middle and tapering towards each 

 end ; the upper ends terminate in short, smooth, oscular collars, and the lower ends 

 are rounded off. The whole sponge, except the oscular collar, is covered by a 

 meshwork of projecting spicules which give the surface a bristly honeycombed 

 appearance (see Figs. 10 and 81). 



The dimensions of the four specimens are as follows : — 



Length. Maxinmm diameter. 



60 mm. .... 15 mm. 



37 mm 7 mm. 



50 mm 5 mm. 



37 mm. . . . . ' 9 mm. 



All the specimens are white in colour as preserved in spirits. 



