184 DE. C. T. TEECHMA]S'X OX [vol. IxXlii, 



DiSCOPHTLLITES cf. EBNEEI MojsiSOvicS. (PL XVII, fig. 7.) 



1896. Fhylloceras {Ilojsva rites) ehneri ' Obertriadische Ceplialopodenfauna des 

 Himalaj^a' Deuksclir. k. Akad. Wissenscli. Wien, vol. Ixiii, p. 668 (96) &■ 

 pi. xix, fig. 6. 



1306. C. Diener, ' Fauna of the Tropites Limestone of Byans ' Pal. Ind. ser. 15, 

 vol. V, Alem. 1, p. 173 & pi. v, fig. 5. 



Shell smooth or exhibiting faint growth-lines ; whorls gently 

 rounded, increasing rather rapidl}^ ; the umbilicus wide and open, 

 each whorl embracing about half the previous one. Umbilical 

 shoulders in the more adult shell are rounded and rather over- 

 hanging. The earlier whorls are much flatter than the later, which 

 in very large specimens become much rounded. 



Locality and horizon. — Bed c, Otamita (Hokonui .Hills). 

 The fragment illustrated occm-red near the JSIytilus-'problematicus 

 Bed, south of the Wairoa Gorge, Nelson. In the Geological 

 Survey Collection is a magnificent specimen from Nugget Point, 

 measuring 18 inches in diameter. Carnic. Large Discopliyllites 

 are recorded from New Caledonia. 



Remarks. — DiscopliyUiteB is a sub-generic name proposed 

 by Hyatt for a group of forms connecting MonophyUites and 

 Rliacophyllites. The peculiarities of the suture are said to be 

 that the siphonal lobe is deep and narrow, and divided by a high 

 median prominence, and the siphonal saddle is diphyllic. Three 

 species have been described: D. patens Mojsisovics, from Europe; 

 I), ehneri Mojsisovics, from the Himalayas; and D. insignis Gem- 

 mellaro, from Sicily. Prof. Diener remarks that all three form a 

 well-defined and closely-allied group ranging from Middle Carnic 

 into Lower Noric strata. The New Zealand form seems to agree 

 closely with the Himalayan D. ehneri. 



AULACOCERAS sp. (PL XVII, figs. 4 & 5.) 



1878. Belemnites otapiriensis Hector, Trans. N.Z. Inst. vol. x, p. 485. 



In one example the end of the guard and the anterior part of the 

 phragmocone are both missing. The guard is soft and friable, and 

 there are one or more longitudinal grooves on it. The phragmocone 

 is nearly twice as long as the guard, and has eleven or twelve air- 

 chambers remaining. The septa are irregularly spaced, and the 

 siphuncle is marginal. A label attached to this specimen (which is 

 figured in PL XVII, fig. 4) states that it is the holotype of Hector's 

 Belemnites otapiriensis. A highh^-idealized illustration of this 

 specimen, which Hector caused to be printed, has recently been 

 issued.! It is 150 mm. long. 



Another specimen consists of a fragment of a guard in very hard 

 greywacke, which, Avhen dissolved out with acid, yielded a gutta- 

 percha squeeze (illustrated in PL XVII, fig. 5). About half the 

 surface is seen, and has th/ee longitudinal ribs separated by two, 

 sharp and deep furrows. The surface of the ribs is gently rounded, 



^ Bibliography, 47, pi. v, fig. 1. 



