90 
RECORDS OF THE AUSTRALIAN MUSEUM. 
* DENDRO T ROC HUS, Pilsbry , ASSIGNED TO 
T ROC HO MORPH A . 
By C. Hedley, F.L.S. 
[Plate XXI.] 
From considerations of shell characters, and perhaps of geogra- 
phical distribution, Pilsbry attached f to the genus Papuina , a 
compact and newly defined group, Dendrotroclius , embracing the 
species kindred to (Helix) helicinoides, Hombron and Jacquinot. 
The author of it added that the soft anatomy of the section was 
unknown to him. 
Some examples of the animal of the type species collected by 
Dr. Y. Gaunson Thorp, of H.M.S. “Penguin,” presented by him 
to Dr. J. C. Cox, and transferred by the latter to the Australian 
Museum, have just been examined by myself. The result is to 
convince me that at least T. helicinoides , and probably the species 
Pilsbry associates with it, must be dismissed from the genus 
Papuina , and be ranked under the genus Trochomorpha. Those 
features in which Dendrotroclius leans from Trochomorpha towards 
more normal Zonitidse, namely the tripartite sole, caudal mucous 
pore and side cusps of the rachidian tooth, induce me to hold it 
as eloser than Trochomorpha proper to a primitive stock. The 
evidence furnished by the foot, dentition and genitalia of Den- 
dr otrochus harmonise, in the classification I propose, with those 
characters of its shell which are emphasied in the diagnosis of the 
section. On page 1 of the work above cited, “ columellar margin 
arcuate, short, not dilated or reflexed, 1? is italicised as an important 
distinction of Trochomorpha ; while on page 143, “columellar lip 
not expanded or reflexed ” is given similar prominence in the 
description of Dendrotroclius . 
Tt is a matter of regret to the writer that his inquiries should 
have led him to mar with corrections a single page of so brilliant 
a work as Pilsbry’s “ Guide to the Study of PLelices but the 
progress of knowledge thus exacts its dues as we rise, to para- 
phrase the poet, on stepping-stones of our dead classifications to 
higher things. 
* Since this article was in print, I have received a letter from Mr. 
Pilsbry, discussing this classification. Accepting the proposed reform, 
he points out to me that Stoliczka described (Journ. Asiat. Soc. Bengal , 
xlii., Pt. ii., p. 20) a rudimentary tail pore in Sivella. From my des- 
cription he now considers “ that Dendrotrochus is an arboreal section or 
subgenus of Trochomorpha retaining an old character in the tail pore.” 
+ Man. Conch. (2) ix., p. 143. 
