Br. J. W. Gregory — On Palceozoic Starfishes. 341 



the posterior end being entire. It appears to have consisted of 

 eight principal ridges, with a 'talon' ridge behind and a subordinate 

 ridge in front. Five of the ridges have been in use, the anterior 

 two in the section being worn down close to the common base of 

 ivory, while the three last ridges are entire. Like the upper molar 

 of ii', ganesa (already referred to), it bears a close resemblance to the 

 corresponding inferior tooth of E. insignis (pi. iv, fig. 1, op. cit.) 

 in the form of the ridges, thickness of enamel, and proportion of 

 cement. This specimen measures about 7^ inches in length (see also 

 op. cit., vol. i, p. 424)." In the same work,^ he describes (pi. xx a, 

 figs. 1 and la) a "Lower jaw with first and second true molars, 

 of Elephas ganesa (Falc. & Uaut.), from the Sewalik Hills. Proved 

 to be so by fig. 2. A most remarkable jaw, very high in front and 

 with very divergent rami behind ; diastemal edges very sharp ; two 

 outer mentary foramina on right side. The front tooth much worn ; 

 has five ridges and a heel ; the last tooth has eight ridges." Falconer 

 adds, " Nothing else like this in the collection, JB.M." 



Extreme length of jaw, 18-5 in. Height at alveolus, 8'5 in. 

 Width of jaw in front, 4 in. Width of jaw behind, 5-8 in. ! Length 

 of front tooth, 5-1 in. Width, 2*7 in. Length of last tooth, 9-3 in. 

 Width, 3-2 in. 



Figs. 2 and 2a. — Elephas ganesa. Portion of lower jaw with 

 left penultimate lower molar. The jaw in this specimen is also 

 very high and narrow in front and low behind. The tooth has 

 seven ridges and a heel. Behind it is seen a portion of the last 

 molar. B.M. Length of fragment, 14-5 in. Height at alveolus, 

 8-3 in. Height behind, 5-8 in. Width in front, 3-3 in. Width 

 behind, 6-6 in. Length of molar, 9-2 in. Width at back, 3 in. 



EXPLANATION OF PLATE XIV. 



Figs. 1 and 2. — Elephas ganesa, Falc. & Caut. Fig. 1, front view, and Fig. 2, 

 profile, of skull and tusks, as no-w exhibited in the Geological Gallery of the 

 British Museum (Natural History), Cromwell Road. The specimen measures 

 144 feet in length. From the Pliocene of the Sewalik Hills, India. Presented 

 by General Sir William Erskine Baker, K.C.B., 1848. 



11. — On Zindstbomaster and the Classification of the 



Palzeasterids. 



By J. ^Y. Gregory, D.Sc, F.G.S. 



(PLATE XYI.) 



THE classification of the Palaeozoic starfishes has long been in 

 chaos. The earlier palgeontologists, who founded most of the 

 known genera, made no attempt at a general classification or 

 to indicate the relations between the Palaeozoic and existing 

 representatives of the Asteroidea. The first step towards progress 

 was Bronn's- division of the extinct genera into three groups — the 

 Ophiurasteriee (which may be left out of account as Ophiuroidea), 

 the Encrinasteriaa, and the Asterite verse. The last two groups have 



^ Falconer & Cautley's "Fauna Antiqua Sivalensis" (the figures of which are 

 described in Falconer's "Pal. Memoirs," 1868, vol. i, p. 452). 

 - H. G. Bronn : Classen xmd Ord. Thierreichs, vol. ii (I860), pp. 287-8. 



