278 BULLETIN OF THE 
description any character not agreeing with the Odonata, except the du- 
bious cells of the front margin, and these are nowhere mentioned in the 
description. 
The small portion of the reverse, which I have examined, is a triangular 
fragment 20 mm. long and 2 to 8 mm. broad. It belongs to a part of the base 
of the wing, which is not preserved in Fig. 8. It does not reach the costal 
margin, and contains several sectors crossed by a straight vein (sector trigonuli 
inferior) similar to the arrangement in Isophlebia. The reverse strongly 
confirms my determination. This sector is to be found only in Odonata, never 
in Ephemeride. The specimen was probably a hind wing. 
Lithentomum Harttii. 
I have examined the type (Fig. 3) of the Boston Society of Natural History. 
It is very difficult to determine the fragment. A part of the base and of the 
lower part of the wing lies below (or perhaps above, as some fragments seem 
to indicate) a Calamites. The base with the stronger triangular basal attach- 
ment of the wing is seen on the other side of the plant. There are strong indi- 
cations that the other wing of the same side lies below this wing, and the 
margin of it a little before the margin of the fragment that is figured. A deeper 
linear impression on the opposite side of the Calamites makes it probable that 
here the upper wing of the other side of the insect may be in the slab. The 
fragment is 36 mm. long; the breadth (at 24 mm. from the base) is 15 mm., 
where a very short portion of the hind border is to be seen. Farther off the 
hind border is broken, so that at 32mm. from the base only 9 mm. of the 
The veins are very faint, and in some parts the veins of 
the underlying wing make them somewhat uncertain. In the costal space 
some very weak oblique cross veins are visible. What is to be seen of the 
longitudinal veins, of their forms, and of some oblong cells between them, 
at both ends, reminds us of the venation of the actually 
The base of the externo- 
1 is to be found in the 
breadth is preserved. 
which are contracted 
living Sialids, and more of the Chauliodes type. 
median shows above and below an arrangement whicl 
wing of Chauliodes. The other parts of the venation give no help for a 
nearer determination. The paucity of the off-shoots of the scapular branch is 
by no means exceptional, as the author believes; the living Chauliodes pos- 
sesses only one, the character claimed by the author for his new family Croni- 
cosialina. Therefore I do not understand why we should consider the fossil 
species as a precursor of the Sialina, before a better knowledge of the species 
supports this suggestion. Fig. 3 is less accurate than the other figures. 
Homothetus fossilis. 
This interesting fragment, of which I have not seen the type, shows near the 
tip of the wing some irregularities of the venation, as if a fragment of another 
wing lay above or beneath the specimen. The author declares it to belong to 
