IlSr THE LOWER TEETIAET STRATA OP KEW ZEALAND. 239 



Tetliya, but as a rule tliey are larger than the giobostellates of 

 T. lyncurium, Linn. Spicules of this type are, however, not 

 restricted to Tetliya, for Carter has figured very similar forms in 

 Stelletta glohostellata (Ann. & Mag. Nat. Hist. s. 5, vol. xi. 

 p. 353, pi. xiv. fig. 5e), Detached spicules of the same form 

 are present in the ' Eireria ' dredgings off the S.W. coast of Aus- 

 tralia, at a depth of 2479 fathoms. 



PI. XIV. figs. 18, 18 a, 21. Small giobostellates having from 

 8 to 15 rays. The rays are short, subcyliudrical, truncate or 

 slightly inflated at the extremities. A small specimen is 'Oil 

 mm. in diameter, and the rays "004 mm. in length. A large 

 specimen (fig. 21) measures '015 mm. across, and the rays are '0067 

 mm. in lensth. Spicules similar to the^e are present in recent 

 species of Tethya associated with the larger spicules described 

 above. In Geodia tubei^culosa, Bowk. (Proc. Zool. Soc. 1872, 

 p. 626, pi. 46. fig. 8), there is also a form similar to fig. 21, and 

 the same type of spicule is present in other species of Geodia 

 and Stelletta. 



Fachastrella (a).— PL XIV. figs. 23, 31. Small giobostellates 

 in which the rays are reduced to small, conical, pointed or obtuse 

 tubercles projecting slightly above the surface of the centrum. 

 Diameter of spicules '016 mm. to '02 mm. Spicules of this 

 character are present in the recent Pachasti-ella exostotica, Osc. 

 Sch. (Algier. Spong. p. 16, pi. iii. fig. 12), from the Mediterranean, 

 also in P. geodioides, Carter (Ann. & Mag. Nat. Hist. s. 4, vol. 

 xviii. 1876, p. 407, pi. xiv. fig. 23 m, o), and in Cydonium esoaster, 

 Sollas (Cliall. Eep. vol. xxv. p. 225, pi. xxi. fig, 23), from Port 

 Jackson. 



Stellate Spicules with Spined Mays. 



PI. XIV. figs. 25, ^Q. Comparatively large stellate spicules 

 with from 6 to 10 elongate conical rays, which are furnished 

 with, stout spines projecting directly outwards. Axial canals 

 are present in all the rays. Diameter of spicules from "09 mm. 

 to '105 mm., length of rays "04 to "055 mm. Spicules of this 

 character do not appear to have been figured in recent sponges. 



PI. XIV. fig. 27. Small stellate with 8 stout conical rays, which 

 are thickly set wdth small spines. Diameter of spicule '03 mm. 

 This form is much smaller than the preceding. 



