444 MR. W.T. BLANFORD ON NEW MOLLUSKS. [June 24, 
valves in Dichelaspis and Conchoderma. In all this we perceive the 
manifestation of, at least, a unity of design, if it be not simply an 
evidence of that latitude for diversity, or the susceptibility of diver- 
gent modification, impressed upon original types by the Great 
Author of Nature. Yet, though we may trace back divergent sub- 
types to one primary source, it would be unphilosophical to expect 
the mutual transmutation of any two such resultants into each other 
as contingent upon what the Darwinian theory is too often incor- 
rectly assumed to involve. For, even if a tendency to revert to the 
original type, such as we see in unstable variety, were to manifest 
itself in any case, the effect of such a tendency would be the pro- 
duction of something very different from the collateral forms, instead 
of running into them, which a superficial thinker might suppose to 
be most natural; for the collateral forms themselves must have ori- 
ginated in special and protracted change developing great, though 
gradual, modification. 
EXPLANATION OF PLATES XXXIII. & XXXIV. 
Prats XXXII. 
Fig. 1. Parodolepas, attached in a group to one of the gills of Neptunus pelagicus. 
Natural size. 
2. a. Group of three of the same little Cirripeds attached to one of the gill- 
flappers. Considerably enlarged. 
6. Lateral view of the single ovigerous lamella. 
ec. Front view of the same, showing the emargination of its anterior 
border ; also considerably enlarged. 
3. Magnified view of Parodolepas neptuni, showing the course of the lines 
of growth, the shelly thickenings, and the minutely dotted surface of 
the valves. 
a. Pedicle. 
6. Scutum. 
ce. Tergum. 
d, Carina. 
Piatr XXXIV. 
Highly magnified view of the oral apparatus of Parodolepas neptunt. 
a. Shelly support of the scutum (occludent segment). 
6, Occludent margin of the capitulum, showing lines or increments of 
growth decreasing both in thickness and length from before backwards. 
ce. Labrum with minute dental points on its angular edge. 
d. Palp. 
e. Mandibles. 
f. Maxilla. 
g. External maxille. 
A. Anterior pair of cirri. 
6. Descriptions of new Land and Freshwater Molluscan Spe- 
cies collected by Dr. John Anderson in Upper Burma 
and Yunan. By W.T. Buanrorp, F.G.S., C.M.Z.8., &c. 
The following are the principal novelties in the large and very 
interesting collection made by Dr. John Anderson when accompany- 
