100 HYDROCAMPA NYMPH^-ATA. 



roots of the Myosotis bared by the action of water, 

 but always fixed edgewise ; indeed, the only excep- 

 tion was in a case fixed flat against a piece of Spar- 

 g anium. 



After the larva had spun up, from seventeen to 

 twenty days elapsed before the appearance of the 

 imago ; I bred seventeen specimens in all at intervals 

 from the 21st of June to the 26th of August. 



Fortunately for our knowledge of the interesting 

 early part of the economy of Hydrocampa nymphceata, 

 Mr. Jeffrey detected amongst some Potamogeton nu- 

 tans, gathered promiscuously as food for his larva?, a 

 large leaf having eggs deposited on the under surface, 

 but without the least covering ; and cutting off the ex- 

 treme tip of the leaf on which were six eggs, for him- 

 self, most kindly sent me, on the 8th of August, the 

 rest of the leaf, bearing about a hundred eggs of a pale 

 ochreous-greenish colour, close together in a flattish 

 mass near the margin from which the tip had been 

 severed. Three days later, by the aid of a lens, I could 

 see two black specks on each egg, and in two more 

 days these were distinct enough, and the day after 

 that, the 14th of August, the larva? all hatched, and 

 soon hid themselves by mining into the under-side of the 

 leaf, not, however, before I had observed and noted 

 their black heads and collar-plates, with pale greenish- 

 yellow translucent bodies. On the same day Mr. 

 Jeffrey was watching the six eggs he had retained, 

 having placed the severed bit of leaf on the upper 

 surface of a fresh gathered leaf put in water, and 

 about 8 a.m. saw the little creatures leave the egg- 

 shells, and crawl over the upper surface of the fresh 

 leaf, and from thence to the under surface, which they 

 at once entered by mining on either side of the mid- 

 rib near the base. In this manner my young brood 

 remained ensconced from thirty hours to three days, 

 and began to reappear, at first singly, then several 

 together ; and then each cut out for itself a tiny film 

 from the under cuticle of the leaf, and floated away 



