IN" THE LOWER TERTIARY STRATA OF NEW ZEALAND. 205 



material, and making due allowance for the possibility that in 

 some species more than one form of anchorate may be present, it 

 seems probable that at least twelve species of one or other of 

 these genera are represented. 



Falmate Ineguianclwrate Flesh-Spicules q/Espcrella, Vosmaer 

 (=Esperia, Nardo). 



I^sperella (a). — PI. X. figs. 1, 2. Large, robust, inequian- 

 chorate with slightly curved shafts, somewhat thicker near the 

 larger end. The lateral palms curved and extended inferiorly 

 to an acute point, directed inwards, outer margins strongly 

 reverted ; anterior palm tongue-shaped, the broad end slightly 

 projecting above the general curve of the head, tubercle pear- 

 shaped. Smaller end of the spicule narrow, the lateral palms 

 with revert margins, tubercle nearly oval. Length of spicule 

 •175 mm., of anterior palm "075 mm., width of larger end '085 

 mm., of smaller "06 mm., greatest thickness of shaft -035 mm. 

 The axial canal is well shown traversing the shaft from the lower 

 to the upper tubercle. In general form this spicule closely 

 resembles the large inequianchorates of Esperia diapTiana, 

 Osc. Sch. (Atlant. Spong. p. 57, t. iv. fig. 13), but if Schmidt's 

 measurements of these are correct, the Oamaru forms are con- 

 siderably smaller. 



Esperella (b). — PI. X. fig. 3. Inequianchorate with large 

 upper end, the lateral palms evenly curved, rounded inferiorly 

 and not extended, the margins reverted, anterior palm elliptical, 

 tubercle elongate pear-shaped ; the lower end of the spicule 

 subquadrate, anterior palm extending nearly the whole width, 

 tubercle subtriangular. Length of spicule 'OSG mm., of larger 

 end "051 mm., width of same "04 mm., length of anterior palm 

 •043 mm., length of smaller end of spicule '013, width "023, 

 thickness of shaft '006 mm. This form corresponds with the 

 large inequianchorates in l^speria anceps, lU. syrinx, and E. 

 Lorenzii, figured by Osc. Schmidt (Adriat. Spong. p. 56, pi. v. 

 figs. 5 «, 5, f) a, h, 7 a, b), but the recent forms are somewhat 

 larger, and their larger ends proportionately smaller than in this 

 fossil. 



J£sperella (c). — PI. X. fig. 4. Inequianchorate with large 

 semi-elliptical upper end, having the lateral palms very evenly 

 curved, the margins reverted, and the lower angles slightly pro- 

 jecting ; anterior palm tongue-shaped, produced below the level 



