302 Dr. l. F. spath osr [vol. lxxix, 



been mentioned that in matrix and mode of preservation Phyllo- 

 ceras aff. mediterraneum shows perfect agreement with Ph. cf. 

 polyolcum. The absence of comparable Phylloceras from the 

 Tithonian Spiti Shales and the Argovian beds in Kachh is note- 

 worthy, but large, ribbed Phylloceras have been recorded from 

 Callovian and Argovian beds in the Sula Islands. 



The Upper Jurassic ammonites here described as Aulacosphinc- 

 toides broionei (Marshall), A. sp. indet., and Uhligites hectori 

 Spath are referred to the Tithonian ; but their generic identification 

 is not definite. The veiy sharp ribbing of the Aidacosphinctoides 

 is reminiscent of the typical Spiti-Shale forms of the group of 

 A. infundibulus (Uhlig), and this is especially true of a fragment 

 included with A. brownei and of an example of A. eudichotomiis 

 (Zittel), since sent by the Geological Survey of New Zealand. 

 But there is also great resemblance to the genus Torqtuitisphinctes 

 of the acanthicus zone. This probably includes various forms 

 wrongly cited in geological literature as Perisphinctes eudicho- 

 tomiis and P. contiguus, which are Tithonian Aulacosphinctoides, 

 and Waagen's Perisphinctes bleicheri {jion P. de Loriol) and 

 P. occultefurcatus from the Umia Beds have been provisionally 

 referred by me to the Kimmeridgian genus Torquatisphinctes, on 

 account of their resemblance to typical forms of the torquatus and 

 alterneplicatus type. Unless both outer and inner whorls are 

 preserved, the distinction of the various perisphinctoid genera ma} r 

 be extremely difficult, and the same types- of suture-line, unfortu- 

 nately, recur continuously throughout the Upper Jurassic. 



The same difficulty is found with the form referred to Uhligites. 

 Similar species, generally grouped in Streblites, have a wide 

 vertical range, and W. Kilian l would make it persist into the 

 Hauterivian. The Mexican forms of the group of S. uhligi 

 Burckhardt 2 are probably true Kimmeridgian Streblites, but the 

 secondary (peripheral) costation already foreshadows the rursi- 

 radiate ornamentation of the Uhligites here described. A com- 

 parable form has been recorded from the Sula Islands, where it is 

 associated with Blanfordiceras ivallichi and Phylloceras strigile, 

 two typical Spiti forms, probably of Upper Tithonian age. If the 

 example here described is referred to the Tithonian Uhligites 

 rather than to the Kimmeridgian Streblites, it is on account of 

 the peculiarly undercut external saddle and the comparatively open 

 umbilicus. 



Two more Tithonian ammonites can now be recorded from New 

 Zealand. A specimen from Palmer Creek (Station 16-17), 

 Awakino River, Mokaii District, resembles Uirgatosphinctes 

 discoides Uhlig, 3 but has a distinctly flattened zone on the 

 periphery, and is thus probabby more correctly assignable to 

 Kossmatia {desmidoptyclia group) ; Avhereas another example 



1 ' Lethsea Geognostica : II. Mesozoicum 3, Kreide' i, 3 (1910) p. 338. 



2 Op. cit. (Bol. No. 29, 1912) pp. 51-64, pis. xi-xv. 



3 Op. cit. (Spiti Shales, 1910) p. 337 & pi. lix, fig-. 2. 



