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legs of larval Tenthredinidz and the abdominal tubercles of Diptera, 
which, as in Chironomus and Ephydra, bear hooks, may, instead of 
being new, adaptive characters, be the homologues of the jointed 
appendages of the other regions of the body. 
After reading Graber’s first paper on polypody in insect embryos, 
and Wheeler’s essay, I took it that I should have to abandon the view 
I expressed in my note in the American Naturalist in 1885, and it 
occurred to me that the seven pairs of lateral processes on the first 
seven segments of Lagoa might be so many pairs of pleuropodia. 
These processes we may now consider. 
THE EXTERNAL LATERAL ABDOMINAL GLANDULAR PROCESSES OF 
LAGOA. 
These are present at birth and in all the larval stages and are 
represented by Figs. 10 to 13, also Figs. 1 and 5. 
There are seven pairs of them, a pair to each of the first seven 
abdominal segments. They are situated near to and directly 
behind, but a little lower down than the spiracles and above the 
infraspiracular tubercles. In fact, they occupy the exact position 
of the evaginable glands of Hyperchiria to and Hemileuca maia, etc. 
In shape they are elongated pyriform conical, or digitiform, being 
slightly contracted at the base, and with two slight contractions to- 
wards the free end, and they remind one of the shape of the append- 
ages of insect embryos just when the joints are beginning to appear. 
The free end is conical, rounded and, so far as I have been able to 
discover, imperforate. They are not capable of being retracted 
and appear to be permanently evaginate, since each pair along the 
side of the abdomen is of the same general length and size, none 
being wholly or in part retracted. 
Fig. to. A, a camera drawing, represents the shape in the 
third stage, just before molting ; sZ., spiracle ; the process was on 
the point of being molted and is hollow. JZ represents the pro- 
cess just after evagination, belonging to Stage IV. It is a little 
longer and larger than before (both figures are drawn to the same 
scale, X one-half inch 4 eyepiece) and filled with granules in the 
middle, with narrow linear cells (Ay?) on the outside or cortex 
which remind one of the linear cells in the pleuropodia of Blatta 
figured by Wheeler (PI. i, Figs. 3, 4). It is to be observed that 
thespiracle in this stage (sf.) is nearly twice as large as in Stage III 
(A. sp.). 
