480 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
October show the testes especially filled with ripe products and ferti¬ 
lization (which has never yet been observed) may take place in the fall. 
Oviposition certainly takes place in May and is preceded by eedysis. 
In 1906, 75 individuals were brought in at different times, the first 
on April 3d. These were kept in a basement room with a rather low 
but uniform temperature. No eggs were laid by these animals until 
the month of June when several masses of them were found. No 
mass was guarded by the adult and as a result the eggs were attacked 
by fungi and disappeared. 
Having gained confidence in my ability to recognize the eggs of the 
Symphyla at sight, much time was spent during the season of 1906 in 
looking for these eggs in their natural surroundings. On May 30th 
while carefully looking over a much decayed log which had an unusual 
number of casts of the Symphyla in its crevices, there were found 
three nests of eggs, two with 8 each and one with 9 eggs. These nests 
were brought in with extreme care and the next day two sets of eggs 
were beginning to hatch. The three views of the larvae in plate 36 
were made from specimens of these broods. 
Eggs. 
Myriapod eggs according to Ivorschelt and Heider (’99, vol. 3, p. 
219) are “ surrounded by a vitelline membrane and another structure¬ 
less but firmer envelop, the chorion, which is apparently secreted by 
the genital ducts.” This description is applicable to the eggs of 
Scutigerella. In figures 4 and 5, plate 37, and figure 9, plate 38, the 
roughened appearance of the outer envelope or chorion may be seen. 
The vitelline membrane envelops closely the egg itself and the egg is 
seen as the dark central portion in both figures. Sections show the 
vitelline membrane to be very thin. 
The surface of the chorion is rendered very irregular by a number 
of large or primary ridges connecting with each other and between 
these are smaller or secondary elevations. The primary ridges pro¬ 
ject about 20 fx above the general level of the chorion. The whole 
surface of the chorion is made up of irregular polygonal depressions 
bounded by these primary ridges. Their largest dimension is rarely 
more than 0.1 mm. and usually it is much less. The floor of one of 
these depressions is again roughened by the slight secondary ridges 
