Hyatt.] 326 [April 4, 



genus. Bran. (Gon.) sulcatum, sp. Munst. Ueber Clym. et Gon. 

 pi. 3, fig. 9, ovatum, ibid, pi. 4, fig. 1, lineare, ibid, pi. 5, fig. 1, 

 subsulcatum, ibid, pi. 5, fig. 2, and Ungeri, Munst. Beitr. are 

 all good examples of this genus. The type, Bran. (Gon.) Ixion 

 sp. Hall, Nat. Hist. NT. Y., Vol. 5, pi. 78, which is a close ally, if 

 not identical, with Bran. (Gon.) rotatorium, DeKon. Calc. Carb. 

 pi. 47, fig. 12, has young, ibid, pi. 73, fig. 12, which are similar in 

 their globular shells, and in their sutures to the adults of the more 

 spherical species of this genus. Branc. umbilicatum, sp. Sandb., 

 has external sutures very similar to those of Parodiceras and is 

 mentioned in the description of that genus. 



Munsteroceras, 1 nobis, includes species of the Upper Devon- 

 ian or Lower Carboniferous which resemble Brancoceras closely 

 in form but are more discoidal. The siphonal saddle is small or 

 larval in shape and is developed in the centre of a deep, often 

 straight-sided ventral lobe. The first or primitive saddles are on 

 the venter and spatulate in outline. The magnosellarian saddles 

 are undivided on the sides in the lower species of this group, but 

 a curious and instructive variation takes place in American forms. 

 Munst. parrallelum has the outer suture of the magnosellarian sad- 

 dle depressed posteriorly below the level of the inner suture of 

 the corresponding dorsal saddle. An acute lobe is thus formed on 

 the edge of the umbilicus, and a small saddle rises inwardly from 

 this towards the zone of compression, and is visible near the edge 

 of the umbilicus in Munst. Oweni. In Gastrioceras this lobe be- 

 comes more important, and in Paralegoceras it is a lateral lobe, 

 and plainly visible on the sides. In the upper Devonian, accord- 

 ing to Hall, we find Munst. parallelum, nobis, equals Oweni var. 

 parallela, Hall, Nat. Hist. K Y., Vol. 5, pt. 2, fig. 1, 2, pi. 73, the 

 members of this genus are Munst. (Gon.) Whitei, nobis, equal 

 Oweni, sp. White, Geol. Ind. Ann. Rep. 2, 1880, Pal. pi. 7, fig. 3, 

 4 (Gon.) tumidum, sp. Roem. Paleontogr. Vol. 3, pi. 13, fig. 3, 4 

 (Gon.) implicatum, sp. Phill. Geol. York. pt. 2, pi. 19, fig. 24, 25, 

 reticulatum, ibid, fig. 26-32, excavatum, ibid, fig. 33-35, compla- 

 natum, DeKon. Calc. Carb. pi. 46, fig. 4, inconstans, ibid, pi. 48, 

 fig. 4-9, truncatum, ibid, pi. 48, fig. 2, 3, implicatum, ibid, pi. 50, 

 fig. 2. The forms are all more involute than Munst. Whitei, 



1 Dedicated to the memory of Georg, Graf zu Munster. 



