IRLAKONDA— JAIPURITE. 59 



are said to be separated from the Kama, clays of trie Pegu system 

 by an unconformity. These " Marine Irrawaddy " beds were 

 afterwards distinguished by Stuart under the name Akauktaung 

 series (Director's General Report, Rec. Geol. Surv.Ind., XLI, 79, 

 1911). The lowest beds of the Irrawaddy system near 

 Yenangyaung contains a fauna which, according to G. E. 

 Pilgrim (Rec. Geol. Surv. Ind., XL, 196, 1910), is of Middle 

 Siwalik age, or equivalent to the Pontian (Upper Miocene) of 

 Europe. The age of the basement unconformity in Lower 

 Burma is estimated by Stuart (loc. cit., 278) to be about Upper 

 Tortonian (Middle to Upper Miocene) in age, and he correlates 

 it with Noetling's so-called " Anoplotherium birmanicum zone " 

 of Upper Burma. 



Jabalpur group.— Named from the town (23° 11'; 80° 0') by T. Oldham 

 (Rec. Geol. Surv. Ind., IV, 75, 1871) for a series of beds origin- 

 ally recognised by J. G. Medlicott in the Narbada valley (Mem. 

 Geol. Surv. Ind., II, 176, 1860), and distinguished by him as 

 Upper Damuda. The group consists of clays, shales and earthy 

 sandstones with some thin seams of coal. Limestone is rare. 

 The beds are unconformable on the lower Damudas and contain 

 a very different flora. They are probably conformable on the 

 underlving Mahadewas. The flora examined by 0. Eeistmantel 

 (Rec. Geol. Surv. Ind., IX, 125, 1876, Pal. hid,, XI, 2) shows 

 an affinity both with the Rajmalial and Umia beds of Cutch 

 and is probably intermediate between the two in age. 



Jabbi Stage. — A stage of the Upper Productus Limestone of the Salt 

 Range, so-named by W. Waagen (Pal. Ind., Ser. XIII, Vol. IV, 

 Part 2, 241, 1891), in the Shahpur district. Also referred to in 

 his memoir as the Cephalopoda bed and regarded as Upper Permian 

 in age. 



Jadeolite. — Xame suggested by G. F. Kunz (Min. Ind, for 1907, 

 Vol. XVI, 810, 1908) for a dark-green chromiferous syenite said 

 to be found at a jadeite mine near Bhamo, Upper Burma. 

 Possibly pseudo- jadeite (q. v.). 



Jaipurite. — The name probably intended for the mineral described 

 as Syepoorite by J. Nicol (Man. Min. 1849, 458) on the assump- 

 tion that the specimens came from " Syepoore," a probable type- 

 graphical error for ' Jyepoore.' Major W. A. Ross (Proc. Roy. 

 Soc, XXI, 292, 1873) corrects the name and refers to the mineral 

 as a " sulph-antimonial arsenide of cobalt," but his analysis, 



