Weller — Kinderhook Fanned Studies. 107 



men which is here illustrated for the first time. Its generic 

 position is by no means certain, so it is retained in the genus 

 Loxonema where it was originally placed. The shell probably 

 posesses no umbilicus as is indicated by the original descrip- 

 tion quoted above, though this cannot be determined with 

 entire satisfaction from the type specimen. The description 

 of the surface markings is also somewhat misleading as the 

 specimen is almost absolutely smooth with the exception of a 

 few faint lines of growth near the aperture. There are not 

 six volutions preserved in the t}'pe specimen, though there 

 may have been that number in the perfect shell. 



Loxonema sp. 



PL VII. f. 2. 



Among the specimens labeled Murchisonia quadricincta in 

 the University of Michigan collection, there are several indi- 

 viduals which have a more elevated spire than the type of that 

 species, with smooth, rounded volutions which are but barely 

 in contact, the lower volutions not overlapping the upper. 

 These shells evidently belong to the smooth shelled division 

 of the genus Loxonema, though they are not sufficiently well 

 preserved to determine their essential characters. 



Murchisonia quadricincta Win. 



PL VII. f. 3. 



" Shell of medium size, turrited; whorls convex, regularly 

 enlarging to the last, with an obsoletely bicarinate band run- 

 ning along the middle, below which are four small, rigid, 

 thread like approximated carinae, leaving the base of the body 

 whorl smooth or faintly lined, and regularly curved into the 

 umbilical cavity ; the surface above the band marked only by 

 very delicate lines of growth, which arch backwards to the 

 peripheral band, below which they arch far forwards, entering 

 the umbilical cavity half their length in advance of their place 

 of origin at the suture. Suture deeply impressed. The only 

 specimen showing the external markings has a defective spire, 

 but could not be completed with less than 8 or 9 whorls, 

 giving a length of 27 mm. ; an apical angle of 19°, a sutural 

 angle of QQ°, while the body whorl is 6 mm. high." 



