70 THE ENTOMOLOGIST. 
preparing for another moult, which, after four days’ torpidity, 
was completed during the night of the 7th. I had carefully 
recorded all the moults, so that there seemed no possibility of 
error, though to me the fact appeared without precedent.* 
LARVA.—6th age. (Fig. d.) 
The ground-colour is now a delicate, soft pea-green, which towards the 
back becomes more and more white, owing to an exceedingly fine coating 
of the farina. The pre-anal shield is flat, thick, and horizontally extended ; 
it is tinged with blue. All the tubercles have the form of short, soft, 
slender spines, beset very sparsely witb minute spicule. These organs 
are of a lively azure hue, which is concealed to some extent by a coarser 
exudation of the farina, which clogs irregularly about them, like damp 
flour. The two upper tubercles on the eleventh segment are, as usual, 
united into one, thick, and medially placed. The middle one on the same 
segment is reduced toa mere wart: the lowest is normal. ‘The prothoracic 
tubercles are azure, as all the rest, but are tipped with shining blue-black ; 
the upper and middle meso- and metathoracic tubercles appear as if cut off 
just above their bases, each leaving a sort of wrinkled scar, of azure hue. 
Feet azure; the terminal joint polished black, whence a black line runs 
up in front of the higher joints. Prolegs azure, crossed by two bands of 
polished black, and terminated by a soft margin of pellucid purplish green, 
which carries the clinging hooks: the space between the two black bands is 
azure, and this space is set, at the lower margin, with a row of fine short 
white bristles, curving downward. The hindmost bear, each on its upper 
and outer portion, the usual triangular mark, which in this case is sub- 
* The variation, however, is not so unprecedented as I at first supposed. 
Porter (Silk-manufact., p. 120) speaks of a var. of Bombyx mori, ‘“ which casts its 
skin only thrice ;” and Capt. Hutton (Trans. Ent. Soc., 3rd ser., p. 299) refers to 
the same, which, however (p. 311), he considers a distinct species. Both refer to 
Count Dandolo, as their authority for the fact. M. Bavier (La Sericicult. au Japon., 
p- 8) says, “ Les vers japonais traversent les quatre mues, a l'exception d’une race 
. . . qui file le cocon au bout de la troisi@éme mue.” 
Burmeister (Man. Entom.; Shuckard’s transl., p. 431) observes that the cater- 
pillars of some of the larger moths moult very frequently: “* for instance, Aretia 
villica, from five to eight times; A. dominula, nine times; and A. caja ten times.” 
In the case of my Atlas larve, as I had but one that attained this maturity, I 
might have supposed it accidental and abnormal. But a gentleman, who also has 
essayed the rearing of this species from larve of the same brood as my own,— 
Mr. Thomas Edmonds, of Bedford Row,—confirms my experience. He observes, 
“T feel sure that mine have moulted five times, and are in their 6th age, as yours 
are.” Mr. Edmonds mentions that he has reared two broods of Samia Promethea, 
of both of which the larve moulted three times only. On the contrary, my own 
experience of Promethea gives them the ordinary number of four moults. 
