IN THE LOWEK TEETIABT STEATA OF I«EW ZEALAJSTD. 201 



AncTioraie Flesli-Spicules ofMyxilla, Desmacidon, and 

 allied Genera. 



Myxilla ? (a). — PI. IX. figs. 41-44. Equiancliorate spicules 

 with stroDgly curved shafts, aud elongate, acutely-pointed teeth. 

 Average leugth of spicule '071 mm., of the teeth '017 ; thickness 

 of shaft '01 mm. 



Myxilla (b). — PI. IX. fig. 48. Equianchorate with relatively 

 short, thick, curved shaft, and three simple teeth at each end. 

 Leugth of spicule "026 mm., of teeth '0083 mm., width across 

 teeth '013 mm., thickness of shaft "007 mm. This form is of the 

 same character as that shown in fig. 40, but the shaft is not 

 inflated. Somewhat similar anchorates are present in Myxilla 

 com^pressa, E-idley and Dendy (Chall. Eep. vol. xx. p. 139, 

 pi. xxvii. fig. 9 at), from off the mouth of the Eio de la Plata, 

 (jOO fathoms. 



Pi. IX. figs. 49, 50. Spicules with strongly curved, stout 

 shaft and prominent curved teeth ; the lateral teeth at either end 

 of the spicule are extended so as to form claw-shaped, processes. 

 In size the spicules correspond wdth the preceding (fig. 48), 



PI. IX. fig. 53. Equianchorate spicule with strongly curved 

 shaft and short stout blunt teeth, which openly diverge from 

 the shaft. Length of spicule "031 mm., of teeth '012 mm., 

 thickness of shaft '0053 mm. This spicule is of the same type 

 as the foregoing (figs. 48, 49, 50), but it is larger, and further 

 distinguished by the blunted character of the teeth and their 

 open disposition. 



Myxilla (c). — PL IX. fig. 45. Equianchorate with stout even 

 shaft, ends triangular, the lateral teeth nearly straight, margins 

 infolded, with prolonged incurved, hook-lilie extremities. An- 

 terior teeth narrow, elongate. Length of spicule "037 mm., of 

 lateral teetii "013 mm., thickness of shaft "017 mm. Similar 

 spicules are present in Myxilla arhorescens, Ridley ('Alert ' E-ep. 

 p. 430, pi. xlii. fig. a"), from shallow water at Port Jackson, but 

 their shafts are less robust and the lateral teeth obtuse. 



Myxilla (d).— PI. IX. fig. 46, PI. X. figs. 46, 47. Equian- 

 chorates with robust shaft aud regularly curved simple teeth. 

 Length of spicule '031 mm., of the teeth "Oil mm., width across 

 teeth '016 mm., thickness of shaft -005 mm. ; PI. X. fig. 47 is 

 a lateral view of probably the same spicule. These spicules 



