IN THE LOWER TERITARY STRATA OF NEW ZEAL^VND. 193 



but they are rare forms, and considerably larger than those pre- 

 sent in this deposit. Detached acuate spicules occur in dredg- 

 ings off the S.W. of Australia, taken by H.M.S. ' Egeria ' from 

 a depth of 3000 fathoms. 



Spinulate or Pin-shaped Spicules of various Genera. 



PI. IX. fig. 1. Stout elongate spicule, with evenly rounded 

 head and smooth straight shaft, neai'ly cylindrical in the upper 

 half, then tapering to an acute point. The axial canal witli a 

 slight inflation at the head, continuous throughout tbe shaft, and 

 opening at the apex. Length I'OG mm., thickness "03 mm. 



Stiherites (a). — PI. IX. fig. 2. Shaft straight, elongate, slender, 

 smooth, and fusiform; head small, conical, constricted at the 

 neck. Length '425 mm., thickness "013 mm. Very similar 

 spicules occur in Suherites senilis, Eidley and Dendy (Chall. Hep. 

 vol. XX. p. 209, pi. xlv. fig. la), from the North Pacific, at a 

 depth of 2050 fathoms. 



PL IX. fig. 3. Stout, smooth, straight; head rounded, slightly 

 constricted neck, very gradually tapering shaft, acutely pointed. 

 Length 1-21 mm., thickness "03 mm. 



PL IX. fig. 4. Spicule straight; bead rounded, with promi- 

 nent spines ; shaft gradually tapering, furnisbed with a few small 

 spines. Length '305 mm., thickness "012 mm. 



Crihrella (a). — PL IX. fig. 5. liobust, slightly curved, spi_ 

 nulate ; bead evenly rounded, bulbous, not distinctly marked off 

 from the shaft, which gradually tapers to an acute point ; the 

 bead and the upper third of tbe shaft covered with stout, pro- 

 minent, conical spines ; the rest of the shaft smootb. Length 

 •35 mm., thickness at summit "045 mm. A similar, but somewhat 

 smaller, spicule is figured by Mr. Carter in Crihrella hospitalis, 

 Osc. Sch. (Ann. & Mag. N. II. s. 4, vol. xviii. 1876, pi. xv. fig. 36 a). 



PL IX. figs. 6, 7, 8. Pin-shaped spicules, with straight smootb 

 shafts ; beads evenly rounded, constriction at neck, tapering in 

 the lower half, acutely pointed. Length "5 to "7 mm., tbickness 

 •02 to '036 mm. Similar spicules are present in Spirastrella 

 transitoria, Ridley ('Alert' Rep. p. 623, pi. liv. fig. g_), from 

 Darros Island, at a depth of 22 fathoms. 



PL IX. figs. 9, 10, 11. Smooth, slender, curved spicules, with 

 prominent evenly rounded beads, and shafts of the same thick- 

 ness for tbe upper two-thirds, below this tapering to an acute 

 point. Length "18 to '4 mm., thickness '005 to "01 mm. 



LINN. JOURN. ZOOLOGY", TOL. XXIT. 14 



