part 3] THE teias of kew Zealand. 215' 



exaggerated development of shelly matter in the hinge-area and 

 cardinal process. The group persists into Jurassic times, the first 

 instance known to me of a Spirigerid in the Jm-assic. 



The appearance in New Zealand, on so low a horizon as the 

 Carnic, of brachiopods presenting a decidedly Ehsetic aspect, such 

 as the group of Spirigera oxijcoliios (including the new genus 

 Hectoria), and Sjoiriferince of the group of Sp. suessi and. 

 Sjp. austriaca and others with the Cyrtiniform septal structure, 

 impresses the Upper Triassic Brachiopod fauna of i^ew Zealand 

 with Rhsetic affinities. It suggests that some of the European 

 Rhsetic forms may have originated in the Southern Hemisphere 

 or round the shores of Gondwanaland. On the other hand, a 

 JSLentzelia very like the European Muschelkalk form JSL menizeli 

 occurs high in the Ehsetic in New Zealand. The value of the 

 Brachiopoda for zonal purposes in the New Zealand Trias seems to 

 be limited. 



It is significant to find in the New Zealand Trias certain phyla 

 of the Brachiopoda towards the last stages of their existence- 

 developing an excess of shelly matter in the following respects : — 



(a) In the Spirifei-inx, in the form of extremely-alate shells and corre- 

 spondingly lengthened spiralia. 



(&) In the Mentzelise, as a covering of tubular spines. 



{c} In the Spirigerse, as an enormously-enlarged cardinal process and a. 

 greatly-thickened hinge-area. 



Rastelligeea, Psioidea, a:s'd Clavigeea. 



A few remarks dealing with these subgenera of Hector^ are 

 necessary in discussing the Brachiopoda of the New Zealand Trias. 



Rastelligera embraced a group of alate Spiriferince, having a 

 row of vertical rake-like teeth arranged along the hinge-area. The 

 comb-tooth structui-e is certainly very apparent in many of the- 

 New Zealand BpiriferincB, but especially so in the very alate form 

 that I have called Sinriferina diomeclea. Since, however, it is- 

 visible also in many true SpirifercG of the Palaeozoic, as well as in. 

 ^piriferina^ it cannot be regarded as of generic significance. In 

 some at least of the specimens that I examined I concluded that 

 the shell-surface had been parth'- decomposed and the outer layer 

 destroyed previous to fossilization. This surface-erosion seems to 

 have taken place readily in the coarser sediments. In one specimen 

 the central part of the area showed the comb-like structure ; while 

 towards the wings the outer surface remained, and was longitudinally 

 striate as in an ordinary Spirifer. The structure certainly does 

 not appear on the alate Spiriferina Jtaihikuana of the Kaihiku 

 Series, and in consequence Hector concluded that JRasteJUf/era 

 was absent from those beds ; but I am inclined to think that the 

 greater fineness, or more rapid deposition, of sediment in those 

 beds prevented the surface-decomposition of the shell. 



Psioidea designates, according to Hector, Spiriferince, var34ng 



' Bibliography, 16. 



s2 



