EARLIER STAGES OF CATACLYSTA LEMNATA. 3 



water, are quite wet, and seem quite at home. They cut out 

 irregular portions of leaf of L. trisulea, and get between the 

 loose bit of leaf and the remaining portion. So far there is 

 nothing that can be called a case, i.e. a movable case, and no 

 larva is yet in a tube, or anything of that sort, but is between 

 two flat surfaces, or sometimes three. One larva under L. minor 

 had cut up the short radicle into three or four pieces rather more 

 than his own length, and had fastened them together irregularly. 

 All the larvae that had done anything, and some that had not, 

 had already green matter in the alimentary canal, and it seems 

 certain that portions of plant are cut off by eating the material 

 along the dividing line. 



9 p.m. — One of the floating eggs has hatched, and the larva 

 has reached a bit of duckweed ; his procedure was not observed, 

 but he did not come out on top ; so that the clothed face of the 

 egg is the face of attachment, not the free one, as in such ova as 

 caruleocephala, lanestris, &c. 



There can be little doubt that the eggs are attached to the 

 duckweed by the same face as that covered by the scales in the 

 floating ones. One face of the egg is in the water, the other 

 attached to something. The eggs on the duckweed could no 

 doubt obtain a supply of oxygen from the green plant, the 

 floating eggs from the air, but I incline to think that in both 

 cases breathing takes place by the wet surface, which is the 

 exposed active surface in all other similar eggs ; and were it not 

 so, eggs laid, as must frequently occur, on bits of floating dead 

 vegetation, whether bits of wood or dead Lemna, would be unable 

 to respire. I wondered a good deal about the floating eggs. 

 How were they laid, and how were they coated with scales ? I 

 came to the conclusion that they must be laid by the moth on 

 her own body, and in some way detached, as she has no appa- 

 ratus for coating eggs with scales. No doubt laying the eggs 

 under water on leaves of Lemna is the usual and proper way of 

 laying the eggs. Were the floating eggs the result of some 

 accident by which the moth laid the eggs on herself, or on 

 another moth (there were several in the jar) ? Against this 

 supposition is the fact that the eggs got detached from the 

 surface of the moth, suggesting that it was a normal process, 

 and still more especially that the eggs thus laid, under a layer 

 of scales floating on the water, got on in every respect as well as 

 those on the Lemna. 



June 17th, 8 a.m. — All the floating eggs have hatched, and 

 the young larvae are on the bits of duckweed, against which they 

 floated. Two have eaten so far into leaves of L. minor, that 

 they can be distinguished from the upper side through the 

 thinned centre of the leaf. 



The larvae in their shelters are still in the water ; they have 



r> 2 



