222 MK. A. M. ALTSON ON THE METHOD OF 
A ripe egg removed from the calices of a female does not show the 
process or striations, and would thus agree with Xambeu's (1898) descrip- 
tion of the egg of h. linearis. 
The recently deposited egg (PI. 12. fig. 3) has a distinct granular appear- 
ance, due to the exceptionally large yolk granules. 
The size of the deposited eggs was found to range from 1"25 mm. to- 
0'8 mm. in length without the process, which varied in length from 0*2 mm. 
to 0"35 mm., and the width of the egg ranged from 0"15 mm. to 0"175 mm.. 
During maturation the egg slightly increases in size. 
In eight specific instances, comprising 13 eggs under observation, the 
young larva reached maturity 15 days after the egg was laid. That is^ 
movements of the larva were visible within the chorion at that periods 
The actual number of hours any of these eggs took to reach this stage is not 
known, as the time at which oviposition took place was not observed. But 
the small pieces of wood in which the beetles were allowed to oviposit were 
put in their cages — glass-topped tins — in the evening and collected the 
following morning, 12 to 16 hours later. 
At the time of maturation or when the first movements of the larva are 
visible, it occupies appi'oximately half the length of the egg (PI. 12. fig. 4) 
and is situated in the posterior portion ; the anterior poi-tion, from the base 
of the process to the head of the larva, is occupied by a mass which consists 
of large j'olk granules and fat bodies. The writer has observed that this 
extraordinary mass* constitutes in i. hrunneus the initial food of the young 
larva whilst still enclosed within the chorion. 
In the case of L. planicoUis it is stated that : " In hatching, the larva 
backs out of the egg " (Snyder, 1916). It is the reverse with L. hrunneus. 
So soon as the larva is matured, it commences to eat the residual yolk-mass 
situated in the anterior portion of the egg by means of its mandibles, and 
travels forward to do so. If an egg is completely exposed in the vessel,, 
the larva is unable to consume the entire residual yolk-mass, owing to its 
movements and the lack of " overhead " support— the wall of the vessel — it 
usually breaks the chorion and works its way out of the vessel. But if small 
strips of tissue, such as parts of a medullary ray, are left above part of the 
egg, the larva is able to maintain its position and consume its food, and at 
the same time the observer is enabled to follow its normal movements. 
An examination of longitudinal and transverse sections of a small number 
of eggs in different stages of development, suggest that the phenomenon of 
the residual yolk-mass is due to the blastoderm enveloping only a part of the 
yolk. It was thought that it might be a case of polyembryony, with one or 
more embryos abortive, but there was no evidence found to support this. 
* Owing to the lack of an existing term for this "yolk-mass" — no analogous yolk-mags 
being known — the term residual yolk-mass has been suggested and is used in this paper to- 
denote it. 
