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Transactions of tlie Society . 
naturally supposed that his own and Kramer’s were identical ; he 
knew that Kramer’s genus could not stand but does not seem to have 
known that Kcch’s could not ; he called his species Gelseno segrota, 
falling back on Koch’s name, and he was perfectly correct in saying 
that his species was segrota (judging from his figure) ; but he was, 
in my opinion, incorrect in identifying it with Kramer’s species. 
Canestrini in his later work follows Berlese in adopting the name of 
Gelseno segrota, but as he identifies it with the former description and 
figure of Fanzago and himself, it must be presumed that the species he 
has is really pyriformis. The confusion arises from neither naturalist 
having the two species. There are, however, two species which, although 
closely allied, are clearly distinct ; both are British, and I have several 
specimens of each. The best figure and description of segrota are 
Berlese’s ; the best of pyriformis Kramer’s. Berlese in his descrip- 
tion of the genus Gelseno, published long after his description of the 
species, gives a rough figure of Kramer’s species and says it is segrota 
with the nymphal skin persisting. This seems to me an error, and it 
would not account for the different shape of the genital plate of the 
female. The principal differences are as follows : — 1. The rostrum 
of pyriformis is much broader and more rounded anteriorly than that 
of segrota , and is bordered laterally by horizontal blades of thin 
chitin not found in segrota ; these blades are marked with diagonal 
parallel lines. 2. The median line of the abdomen in pyriformis , 
particularly the hinder part, bears a strong and conspicuous chitinous 
ridge not found in segrota , and there are some minor ridges pro- 
ceeding from it ; on the other hand the anterior part of the body in 
segrota bears a longitudinal median trench well shown in Berlese’s 
figure, but not found in pyriformis. 3. The genital plate (epigynium) 
of the female of pyriformis is narrower anteriorly and broader pos- 
teriorly than that of segrota , which is much more oblong, although 
not quite oblong. 4. Pyriformis is somewhat the larger species. 
Generally distributed in England, but rather rare. 
Observations on the Anatomy of Glyphopsis formicarise, 
plate YII. 
In this Journal, 1889, pp. 1-15, I have dealt with the internal 
anatomy of Uropoda Krameri, and in 1890, pp. 142-52, with some 
variations of the female reproductive organs in other species. I only 
propose here to mention those points in which the present species 
differs from those before described, without repeating what has been 
already said where the organs are nearly similar. 
The Exo-skeleton and Troplii. 
The first remark here is that if the dorsal shield be dissected off 
and turned over so that the inner surface is exposed to view it will 
be seen that the large spoon-shaped depression in the hinder part of 
