Thomson. — Geology of Middle Waipara and. Weka Pass District. 381 



Waiparia abnormis (Thomson). (Plate XXVI, figs. 16-18.) 



1917. Pachymagas abnormis Thomson, Trans. N.Z. Inst., vol. 49, 

 p. 412. 

 This species, which I described in 1915, is characterized by its broad 

 hinge-line and form only slightly more elongate than suborbicular. 



Type locality : Sands interbedded with main Mount Brown limestone, 



cuesta overlooking the Weka Pass. It is also found in the top layers of 



the same limestone at the foot of 'the dip-slope, attaining here a length of 



32 mm. with a breadth of 31mm. It also occurs at Whatatutu (E. de C. 



^Clarke coll.), and in the Awamoan mudstones of All Day Bay. 



Waiparia intermedia n. sp. (Plate XXVI, figs. 13-15.) 



Shell broadly ovate, beak of moderate length, acute, hinge-line mode- 

 rately broad, somewhat curved, sides convex and regularly rounded, front 

 slightly produced. Valves moderately convex, the ventral longitudinally 

 carinate, the carina flattened anteriorly, dorsal valve anteriorly reflected 

 and with a slight anterior sulcus. Beak erect, slightly produced dorsally 

 of the hinge-line, foramen moderately large, submesothyrid, deltidial plates 

 conjunct. Length of holotype, 31-5 mm. ; breadth, 28-5 mm. ; thickness, 

 16 mm. 



This species is more elongate than the former, the two being about 

 equally folded. 



Type locality : Foot of dip-slope, main Mount Brown limestone, Weka 

 Pass. The species is fairly common in this locality, some of the shells being 

 rather more convex and more strongly folded than the holotype. It also 

 occurs in flattened specimens in the Awamoan mudstones. of All Day Bay, 

 the Waikouaiti sandstone, and the Wharekuri greensand (McKay). There 

 are forms still more elongate found in the greensand and mudstones of 

 All Day Bay, and in mudstones at the junction of the Brown River with 

 the Aorere River, Nelson. For these a further species must be set up. 



Genus Neothyris Douville. 



Neothyris campbellica (Filhol). 



1885. Waldheimia campbellica Filhol, Mission de Visle Campbell, 

 pp. 173-74, fig. 7, Nos. 1, 2. 



This species was distinguished by its author from N. lenticidaris on 

 account of its narrower shell and more detached beak. The shell is oval 

 with a strongly curved hinge-line, the beak passing into the sides without 

 an angle. The beak is considerably produced dorsally of the hinge-line, 

 but is erect and not incurved towards the dorsal valve. 



As thus defined from topotypes, the species is common in the 

 Wanganuian. There is one specimen from the uppermost Mount Brown 

 limestone which must be referred here. 



Neothyris ovalis (Hutt.). 



1873. Waldheimia lenticidaris Hutt., Cat. Terf. Moll. Eeh., p. 3^ 



(not of Deshayes). 

 1886., Waldheimia ovalis Hutt., Trans. N.Z. Inst., vol. 18, p. 335. 

 1905. Magellania lenticularis ovalis Hutt., Trans. N.Z. Inst., vol. 37, 



p. 475, pi. xlv, fig. 2. 

 1915. Neothyris ovalis Thomson, Trans. N.Z. Inst, vol. 47, p. 395, 



fig. 2, d, e. 



