MR. LUBBOCK ON THE THYSANURA. 445 
a small swelling at one end, and a larger oval body at the other (PL XLVI. fig. 39) ; 
this, however, is not probably the mature form. 
The testis also contained numerous greenish, oval or somewhat quadrate bodies 
(PI. XLVI. fig. 41), about -0002" in length, and exactly resembling the similar bodies 
which I found in the testes of Chellfer and Obisium, and which so curiously resemble 
the spermatozoa of Tolydesmus. 
There were also a number of larger spherical cells (fig. 42), from -0005" to 001" in 
diameter, and transparent or containing only a few granules. These may perhaps be 
compared with the similar bodies found in the testis of Oniscus. 
The walls of the triangular reservoir are rather thick, and consist of nucleated cells 
(PI. XLVI. fig. 38). It contains the spermatozoa and the green bright bodies, as well 
as some other globules, which resemble oil-globules. 
The walls of the accessory glands are also composed of thick cells. They are com- 
pletely filled by the minute granules, which form an opaque mass. The ductus ejacu- 
latorius has an apparently chitinous lining, which is strengthened, like the tracheae ami 
some other chitinous parts of Articulata, by transverse ribs, which, in this case, are very 
The so-called -gastric tuber and the two filaments which proceed from it, are not the 
least curious part of the anatomy of Smynthvms. The gastric or, as it may better be 
called, the ventral tube is situated on the underside of the body, in the middle line and 
mmediately behind the second pair of legs. From it the animal can project two long, 
manner 
colourless, transparent filaments, which, when extended, are nearly , -th of 
length, are somewhat elbowed in the middle, and at the end are covered with sma 1 1 
vesicles or "glands," which, according to Nicolet, secrete abundantly a mucous fliud by 
which the whole organ is « contiuuellement invisque," but which I have not observed on 
the specimens examined by me. Nicolet gives a figure (pi. 3. fig. 22) of a tentacle, which 
does not altogether agree with my observations ; but, as he does not mention the specie- 
from which it was taken, it is impossible to say that the differences may not be par ly 
specific, thongh I am not disposed to think that they can all be accounted for m this 
... M. Nicolet observes that the tentacles are "doues d'un mouvement rctractil, 
exactement pareil k celui des tentacules oculaires des Limaces ;" but he does not figure no 
describe the very curious muscles by which the apparatus is worked, nor has the sublet 
been investigated by any other naturalist. 
In PL XLVI. fig. 35, 1 give a figure of the whole organ in a state of faction 
point «, the basal portions of the two tentacles, b, b, are attached to the wall of he ventrai 
tube j the tentacle itself is, of course, in this position turned inside out, the outer jnD , A, 
being the inner wall in fig. 36, and the small vesicles seen on the outer wall in that hguie 
being here in the central part of the hollow tube. All the letters m tins figure ^present 
the same parts as in fig. 35 . At the part / is attached the muscle e, wh:ch m fig. 3o he 
iuside the tube, while here it is necessarily external tort. The point , u, the tei nnna 
part of the filament when extended ; the numerous vesicles can be urn. m ** ^rtrf 
position, through the transparent walls, and the muscle « , attached m fig. 34 to the juner 
«de of the extreme end, is turned out in the same manner as the muscle ,. The pomt/, 
At the 
