418 Dr. T. A. Chapman's Contribution to 



size. The plant was cooler at night, but often much warmer 

 by day, when the sun shone, than those I kept in tins. 

 Sometimes the thermometer went up to 90° not directly 

 exposed to the sun. 



On March 18th it is noted : " One or two (in 4th instar) 

 are now and then seen ; one this morning on a petiole is pale 

 green with paler (hardly yellow) dorsal (double) and lateral 

 stripes. They appear to eat, but only very little, between 

 waking up from hibernation and making their third moult." 



March 20th. — Of the ten larvae on growing plant one or 

 two are now and then seen, but they hide very completely. 

 The plant is groAnng vigorously, and has some flower-heads 

 on stems several inches long, down to others that are merely 

 little rough ridges on the growing centre ; many of these in 

 size and appearance closely mimic the young larvae of 

 escheri. I say that the plant mimics the larva, to call 

 attention once more to the fact that unconsciously this view 

 of the matter presents itself to the mind when one is search- 

 ing for the larvae, although one does not for a moment really 

 think so, but knows it is the larva that mimics the plant. 

 In the search, the larva is the rarer, and one probably often 

 misses the larva altogether ; but when one sees it, one is satis- 

 fied and there an end ; but the mimicked portion or aspect 

 of the plant often needs a second glance to make sure it is 

 not a larva, and so for the purposes of our search it is the 

 plant and not the larva that appears to deceive us, and so 

 seems to be the active member of the partnership. 



April 22nd. — The ten larvae have never shown more 

 than one or two at a time, even with the closest search 

 possible, without pulling the plant about. I determined a 

 week ago to remove these ten larvae into glasses, thinking 

 it possible that there might be some Carab, or other depre- 

 dator present that had reduced the ten to two or three, and 

 so to save the remainder. First day secured two, the next 

 day one, again one, on 20th two, this morning one, making 

 altogether seven out of the ten ; the remaining three may 

 have perished, but probably not all of them. Securing 

 seven shows how efficiently they hide on the plant. Two 

 of them are nearly full-fed, one is laid up for fourth moult, 

 the other apparently small in last instar. 



April 24th.— Found a larva (No. 8) this afternoon ; it was 

 high up on a leaf, in much the same position as all the 

 preceding seven were found in ; it is pale, about half-grown 

 in last skin; reminds one much of tliersites, so many of the 



