188 The Phytoptus of the Vine. By Prof. Giovanni Briosi. 
body. It generally moves (raises or lowers) two legs at once, the 
right fore leg and left hind leg, or wice versd, and sometimes (for 
instance, when tired) it assists with its body, putting on the ground 
the anal extremity, which seems to act as a venthole (ventosa). In 
this case the body, bending semicircularly, shortens itself by draw- 
ing in as a leech, and the anus, whilst now nearly approaching the 
head, becomes fixed to the ground (or leaf), whilst the animal, 
using it as a support, lengthens itself by advancing the fore part of 
its body, and repeating the manceuvre. 
This cecidozoid when walking seems to put on the ground 
first the tarsus with its small cylinder, which, contrary to what 
Sorauer assumes (who believes it to be immovable), appears to me 
to be articulated and endowed with vertical motion, which allows 
the animal to assume a quasi normal position in that part on 
which the tarsus itself is inserted, and it is on this that the animal 
supports itself. The feather-like process too is articulated, and 
endowed with a lateral motion. The legs as well as the hind part 
of the body must be furnished with, relatively speaking, very 
strong muscles in order to allow of such a rapid motion. 
Under the line of insertion of the second pair of legs at the 
beginning of the abdomen, exactly after the second or third ring, 
are the genital organs, which outwardly appear as a kind of valve 
or sucker, whichever you may call it, smooth, attached to the skin 
of the body, above, and free below, and terminating in a (circular) 
arc-like curve. 
This valve, sometimes shut, sometimes open, covers the genital 
organs, hiding them almost always from the observer's eye. Once 
only, out of thousands of observations, I happened to see under it 
an oblong slit, around which ran a strong muscular ring, which 
had the aspect of a vagina. 
This detail has not been drawn, because the preparation was 
spoiled ; however, it resembled nearly fig. 6 of Sorauer.* 
In one pair of animals I saw in the region of the genital 
organs a fissure turned upwards. Of the male organs I know 
nothing whatever, outwardly the sexual organs present one and the 
same form in all animals. 
The male, however, appears to be smaller than the female, I 
having several times found two animals closely stretched together 
on their bellies, which I retained in state of copulation (in alcohol), 
of which one invariably was smaller than the other. If, however, 
one does not wish to take into account this difference in size, a 
very uncertain distinction, since even amongst the small animals 
there are some found with eggs, then I would presume to say that 
the male cannot be distinguished from the female with certainty, 
* Handbuch der Pflanzenkrankheiten, Tay. 1%, p. 122, 
