108 



give you any reliable information in regard to the shells referred by Mr. 

 Gabb to Ammonites Newberryanus and A. complexus, var. Suciensis. I 

 remember, however, that I have stated, in my little report on the North- 

 West Boundaiy and Vancouver Fossils, that A. Newberryanus of Gabb is 

 not the form described by me under that name. Mr. Gabb also arrived 

 at the same conclusion after the publication of his report. It is quite 

 probable, as you say, that his A. Newberryanus may be my A. complexus, 

 var. Suciensis." 



3, 4, 5 and 6. Four specimens from the banks of the Trent Eiver, 

 V. I., in Division B, one from above and three from below the falls. Two 

 are about four inches in diameter, and these, though tolerably pei'fect, 

 are somewhat distorted and have much of the sculpture obliterated, as 

 well as some of the finest ramifications of the sutures. The others are 

 about hall" that size, and one of these has the siphonal lobes and saddles 

 beautifully preserved, as well as part of the test. The septation of all four, 

 as far as it can be traced, appears to be exactly like that of Meek's type 

 of A. complexus, var. Suciensis, with which they seem to agree also in all 

 the essential characters, though thc}^ present the following unimportant 

 variations from Nos. 1 and 2 : — They are decidedly more globose ; the 

 height of their apertures, outside of the emargination, being less than 

 the width, in which respect they approach nearer to A. complexus proper; 

 the ribbing is also somewhat stronger than is usual in shells of that size 

 and the ribs curve forwards on the periphery in a series of shallowh'- 

 convex arches; whereas, in No. 1, at least, they cross the siphonal edge 

 in almost a straight line. At first sight, too. the surface seems to be 

 marked by periodic thickenings of the shell, or by corresponding con- 

 strictions or grooves on the cast, which appear to be placed at short but 

 regular intervals. When more closely examined into this appearance is 

 seen to be due to the fact that the ribs which proceed from the umbilicus 

 are broader and higher than those which become obsolete before reaching 

 its margin, and that between each pair of the former there are from two 

 to five of the latter. 



These four Ammonites from the Trent Eiver are almost certainly 

 conspecific with the A. Deccanensis of Stoliczka. 



