126 21ie American (reoloyist. August, 189G 
Family Otonodontida'. CteHodoiitn., Salter {Telliiiomya, Pakeoneilo, 
Hall). It is shown that while the shells described by Hall in 1847 as 
Tellinomya were not clearly defined as to hinge structure, the term 
Ctenodonta, which was better defined, must stand for species which 
have passed current under one or another of the three names mentioned 
and range from the Ordovician to the Trias. While finding no V)asis of 
generic distinction among these forms, Beushausen still recognizes the 
subgeneric value of Pahvonetlo and certain other terms, thus Cteno- 
donta (restricted) includes species with a broad, shallow, obscure sinus 
directed toward the ventral margin: fine concentric sculpture. Type, 
C. nanuta Hall. Palceoneilo: sinus directed more posteriorly, stronger 
and making a distinct emargination of the posterior edge; fine con- 
centric sculpture, often with strong concentric ribs. Type, C. fecunda 
Hall. Koenenia Beus.; the sinus sharply defined by radial ridges. 
Type, C /as//, A. Roem. TancrediopHis,xio\.: anterior portion of shell 
larger than posterior. Type, C. contracta, Salter. Prosoleptus, nov.: 
shell highly inequilateral, abruptly narrowed in front, behind greatly 
widened. Type, C lineata Goldf. All of these subgenera are repre- 
sented in the .35 species here referred to Ctenodonta. The genus is 
somewhat less prolific in tlie American Devonian and is represented by 
only the first two and possibly the third of these subgenera. 
CucuUetla, McCoy. This term is preferred to Nuculites Conrad (older 
by 10 years), from an objection to the etymology of the latter. Such a 
reason rigorously enforced would throw out from nomenclature, to the 
general inconvenience, many useful and long established names. 
Among the synonyms of this genus is placed the term DiiicMa, Sand- 
berger, which was introduced for a small shell having two clavicles, one 
posterior. The author regards this a viniform occvu-rence in the young 
of Cucullella. 
,Ledopsis,Jieu8. Another nuculoid genus with subtriangular outline 
and two radial ridges, one anterior, one posterior departing from the 
beak. Though represented in the German Devonian it has not been 
recognized in American faunas. 
Family Trigoniidie. Mi/ophoria, Bronn. The author follows Freeh 
in referring to this genus the Devonian shells which writers generally 
have embraced under King's genus Sehizodns. Without attempting to 
establish subgeneric differences, which in the opinion of the reviewer 
exist, the author includes his 16 species in four conventional groups, two 
of them suggested by Neumayr. 
Family Astartida?. Cypricardella, Hall. In the shells of this genus 
variously christened Microdon, Eodon, and Microdonella, the author 
notes the presence of a faint second tooth in both valves, and adds that 
these are for the most part faintly developed in Devonian species while 
in Carboniferous species they become very prominent. 
Family Crassatellidie. CrassateJlojJsis, nov. This genus is based 
pon the species C. HaiicJiecoruei, from the Coblenz beds. The valves 
bear a distinct J^lunule in front of the beaks and the general aspect of 
the shell is that of Astarte. The left valve V)ears a strong tooth, the 
