part 3] AMMONITES FROM NEW ZEALAND. 291 



with continuous, though less signioidal costation, differs in, 

 thickness and width of the umbilicus ; but the New Zealand 

 example being slightly crushed obliquely, the opposite side does 

 not show the flexiracliate character, conspicuous in fig. 1 a of 

 PI. XVIII. 



Phylloceras anonymum Haas 1 has similarly continuous cos- 

 tation which, however, is straight, as in the typical Ph. partschi. 

 Dumortier's 3 Ammonites atlas is considerably inflated, and the 

 gigantic Phylloceras ser&plicatum (Hauer) 3 does not acquire its 

 coarse pleating until a fairly late stage. 



The fragmentary example shows the suture-line more clearly 

 than does the figured specimen. This suture-line agrees with 

 that of Phylloceras tenuistriatum (Meneghini) as figured by 

 Fucini. 4 Specimens of this form, however, from Campiglia 

 (British Museum, ex Dr. F. Castelli Coll., agreeing with Pejmes's 5 - 

 fig. 16) have different ornamentation. 



L o c a 1 i t y. — Unrecorded. 



Horizon. — Middle Lias (Doinerian). 



Genus Ehacophyllites Zittel emend. 



Pompeckj 6 suggested that the genus Phacophyllites might be- 

 restricted to the ornamented forms, and 1 7 proposed to take as. 

 typical the group of Ph. transylvanicus-diopsis. 8 Apart from 

 these, many evolute Phylloceratids with diphyllic suture-lines, 

 belonging to various groups from the Triassic Discophyllites 

 upwards, have been included in ' Phacophyllites ', on account of" 

 their narrower whorls, with a correspondingly smaller number of 

 auxiliary elements of their suture-lines. Of these, the Hettangian 

 group of ' Phacophyllites ' stella (Sowerby) could be separated 

 with a new name : Paradasyceras, gen. nov., the genotype to be 

 Phylloceras uermosense (Herbich) Waehner. 9 The constricted 

 inner whorls of P. stella as figured by me 10 and the ' rhacophyl- 

 litic ' suture-line are characteristic ; but attention has already been 



1 ' Die Fauna des Mittleren Lias von Ballino, &c.' Beitr. Pal. Geol. (Esterr.- 

 TJng. vol. xxvi (1913) p. 7 & pi. i, figs. 1-5. 



2 ' Etudes Paleontologiques sur les Depots Jurassiques du Bassin du Rhone *" 

 vol. iv (1874) p. 106 & pi. xxx, figs. 4-6. 



3 Op. cit. 1854, p. 862 & pi. i, fig. 1. 



4 ' Cefalopodi Liassici del Monte di Cetona ' pt. i, Pal. Ital. vol. vii (1901) 

 p. 33, text-fig. 16. 



5 Op. cit. 1879, pi. xliv ; non Geyer, op. cit. 1893, pi. vi, figs. 1 & 2. 



r ' ' Beitrage zu einer Revision der Ammoniten des Schwabischen Jura ' pt. i 

 (1893) p. 39. 



' 'The Development of Trar/ophylloceras loscombi' Q. J. G. S. vol. lxx 

 (1914) p. 355. 



s Lectotype : Phylloceras dio2)sis Gemmellaro, ' Sui Fossili degli Strati a 

 Terebratvla aspasia ' pt. i, Soc. Sci. Nat. & Econ. Palermo (1884) p. 6 & pi. ii, 

 figs. 6-8. 



Wfehner, pt. viii (1898) p. 173 & pi. xxv, fig. 1 only (B.M. C 23140 from 

 Sclireinbach, Wolfgangsee, Austria, ex Panzner Coll.). 



10 Q. J. G. S. vol. lxx (1914) pi. 1, figs. 1-3. 



