82 
PALAEONTOLOGY OF NEW YORK. 
Genus AULONOTRETA, Kutorga. 1848. 
1848. Aulonotreta, Ktjtorga. Ueber die Siphonotretsese: Verhandl. der Russ.-kais. Mineral. Gesellscb. 
^ zu St. Petersb. Jahrg. 1847, p. 278, pi. vii, figs. 10, 11. 
1869. Acritis, Volborth. Ueber Schmidtia und Acritis, idem., 2te Ser. Bd. iv, p. 217, pi. xvii, figs. 7-9. 
The name Aulonotreta was proposed by Kutorga to take the place of 
Obolus, Eichwald, as he deemed the latter an inappropriate name. The first type- 
species under the description is A. polita, Kutorga, which “umfasst folgende, von 
Professor Eichwald, aufgestellte Arten : Obolus Apollinis, 0. Siluricus und ingricus, 
deren unterscheidende Merkmale weder mit Worten, noch mit Zeichnungen 
gegeben werden konnen.”* As O. Apollinis is, however, generally recognized 
as a well-defined species, Kutorga’s first type and his genus, as far as it rests 
on this type, became synonyms for Obolus. The second type, Aulonotreta sculpta, 
Kutorga, is a synonym for the Obolus 
antiquissimus , Eichwald,f and this species 
was taken by Volborth as the type of 
his genus Acritis4 The species is very 
imperfectly known. Volborth’s figures 
indicate a close agreement with Obolus 
in general form, and the characters of 
the cardinal area. The incomplete in¬ 
teriors figured show in the pedicle-valve, a broad, subquadrate median scar, 
crossed on its posterior portion by a transverse band connecting what appear 
to be cardinal scars. In the brachial valve are two subcircular scars in the 
median region just within the posterior margin. In the event of this form 
proving distinct from Obolus, the laws of priority require that it shall bear 
the name Aulonotreta, for which Acritis will then be a synonym. 
* Pp. 281, 282. 
t Urwelt Russl., 1843, p. 142, pi. iv, fig. la, b, c. 
t Loc. cit. . 
Acritis antiquissima. 
After Vorborth. 
Fig. 35. Interior of pedicle-valve. 
Fig. 36. Interior of brachial valve. 
