1921 TUUTWM 49 



Sept. 



what shelly stone, different from Milborne or Thornford Beds— more like 

 latter, but sharp preservation of specimen differs ; S. 29, 43, 67, 31 ; 

 45. 44. 77. 22 ! max ' c - °5- presumably a brephomorph ; EL at II"5, 

 c. 80 per cent., Li, c. 55 per cent. „•_,«., 



M. morrisi, Oppel sp. (Am. macrocephalus, var., Morris & Lycett, 

 1850, Moll. G. O., p. 12 ; PI. 11, f. 3 ; Am. morrisi, Oppel, 1857, Juraf. 

 p 478; Am. viator; Lycett, 1863, Moll. G. O. Suppl., p. 121). The 

 specimen which furnished Morris & Lycett's figure is the holotype of 

 Oppel's species ; but the original figure is misleading : it shows only 

 about 40 ribs, which are much too strong, whereas the specimen has 

 about 60 ribs which are quite feeble. As Morris & Lycett's figures of 

 Am. subcontracts are synthetographs (see above, p. 43), and as they 

 speak of several examples of this species, it may be suggested that their 

 figures in this case are also synthetographs. The rib-characters which 

 they show are those of Morrisiceras, which, however, I have not yet 

 seen from Gloucestershire. If their figures are synthetographs, then 

 their specimens are syntypes, and it will be necessary to choose the 

 specimen now described as the lectotype of Oppel's species : this is in 

 Geol. Surv. England, ex Lycett Coll., no. 25617, from " Minchinhampton, 

 Gloucestershire ; base of Great Oolite," Lycett 1863, cit.— a soft, cream- 

 coloured, crystalline, barely oolitic stone, perhaps the Oven-Bed of Lycett 

 (Cotteswold Hills, 1857, 93, 94) • S. 45. 5L 63, i5'5 I 61. 45- 66, x 5 \ 

 max. c. 85 + , the specimen being septate to the end. 



The peculiar overhanging wall of the gradate umbilicus is not shown 

 by Morris & Lycett : what they have is the umbilicus of Morrisiceras. 

 Sph^ROMORPHITES, n. Macrocephalites Auctt. Genotype, 

 S. sphceroidalis, n. Sphaerocone ; umbilicus narrow, deep, somewhat 

 elliptical, walls superimposed, with tendency to become overhung ; 

 ornament feeble, some undulation on upper edge of inner margin is, 

 presumably, relic of Titlites-st&ge of nodosity ; feebly undulate costulae 

 cross the venter with a forward sweep ; there are signs at intervals of 

 something like constrictions; s.l. simple; EL longer than Li, which 

 at 16 mm. is about 44 per cent., L2 rather long and narrow. England, 

 Dorset. , 



S. sphaeroidalis, n. Cf. Macrocephalites morrisi; Schhppc, Katn. 

 Oberrhein. ; Abh. geol. Spec.-k. Elsass-Lothr., IV (4), 1888, 199 ; 

 vii ; Am. bullatus; Quenstedt, Amm. Schwab. Jura, 1887, lxxvii, 9. 

 Like the early stage of Schlippe's species, but less costate, and certainly 

 not possessing a concave inner margin. Quenstedt's cited figure illus- 

 trates a like, but more narrowly umbilicate, form ; not congeneric as 

 8.1. is different, especially the broad L2. S.B., ex Darell, Coll. 1918, 

 Holotype ; Troll, near Thornford, Dorset ; Fullers' Earth Rock, Thorn- 

 ford Beds, but a matrix distinct from that of the other species, as it is 

 an argillaceous limestone; S. 31.5, 41, 92, (30?); 44- 45. 86 > 2 7 '• 55. 

 51, 84, 20 ; max. c. 75. 



There are further species of Tulitids which do not fit these genera. 

 For instance, Stephanoceras subcontr actum ; Schlippe, 1888, vi, 1, has 

 the shape of Tulophorites, but ribbing comparable with Pleurophontes ; 

 his Macrocephalites morrisi, PI. vn, is doubtfully a Mornsites: fig. I 

 seems to show a concave inner margin, which it is unlikely that Mornsites 

 would develop— if correctly shown in this respect, Schlippe's form belongs, 

 presumably, to a genus between Morrisites and Spfueromorphites. Then 

 the bullati figured by d'Orbigny and Quenstedt seem to indicate several 

 genera ! Am. platystomus globulatiis, Quen., 1887, i.xxviii, 2, is near to 



