ANTHROCERA TRIFOLII StBSP. PALUSTRIS. 503 



variation very small. As the limit towards magnitude of the spots in 

 this species is attained before the limit of A. filipendulae towards 

 obliteration commences, it follows, as a matter of course, that I have 

 never seen any tendency towards the X-like dorsal markings, or ever 

 seen the lateral spots united." Comparing the larva of A. palustris 

 with that of A. filipendulae, Briggs says: "Take a larva of A. fili- 

 pendidae, give it a much clearer and cleaner ground colour, diminish 

 its spots below the limits of the smaller spots in the larva of A. fili- 

 pendulae, so as to make all the pale lines broader, and you will have a 

 specimen of this caterpillar." 



COMPARISON OF THE LARVAE OF A. TRIFOLII VAR. SYRACUSIA AND A. 

 TRIFOLII-PALUSTRIS. Speyer compares these as follows : The larva of 

 A. var. syracusia differs chiefly from that of A. subsp. palustris in the 

 appearance and development of the upper row of spots. In the latter 

 insect each segment carries two spots on either side, whereas in the 

 former these are united into one large one which surrounds a patch 

 of the ground colour. A. var. syracusia also has the front spot 

 belonging to the lower rows lengthened into two points, a character 

 not found in A. subsp. palustris ; moreover, the latter does not have 

 the black streak on the prolegs, whilst the other dark markings the 

 lateral streak, the longitudinal ventral line, and the markings on the 

 anal plate are much weaker, or are altogether absent. One can 

 readily see that these differences, although so noticeable, are simply 

 the result of the dark markings of the larva of A. palustris being more 

 extended in that of A. var. syracusia, and that the latter has thus 

 obtained only one large spot in the upper rows, where the former has 

 two, the spots having joined at their extremities, so as to include a 

 portion of the ground colour. The darkest larvse of A. subsp. palustris 

 are, of course, most like those of A. var. syracusia. 



COCOON. The cocoons measured, average 28-29 mm. in length. 

 They are of a bright yellow colour, fusiform in shape, slightly broader 

 at the upper end where the cocoon is also more brightly coloured, 

 and attached to a grass culm or the stem of some low plant, usually 

 some 12 inches or more above the ground. Sometimes it is flat- 

 tened by being spun on the underside of a broad Iris (or other) leaf. 

 The inside is lined with flossy white silk ; the upper part of the 

 cocoon is very thin, breaking easily to allow the emergence of the 

 pupa, which pushes itself out of the cocoon as far as the 4th 

 abdominal segment, before the emergence of the imago. The empty 

 pupa-case remains projecting from the cocoon. Speyer notes the 

 cocoon as somewhat smaller, and more swollen or vaulted than that of 

 A. fiilipendulae, the upper half of a deep yellow colour, which shows up 

 conspicuously against the almost white lower half in the majority of 

 the cocoons, so much so that the difference is often apparent from some 

 distance. In some it is less distinct, and in others the difference dis- 

 appears altogether. Usually found on grass or Juncus stalks, or the 

 stems of stiff herbaceous plants. [Those of the early A. trifolii are 

 generally placed low down, on or near the ground, and are difficult to 

 find.] Oberthur observes that when the wind moves the grass culms 

 on which the cocoons are spun, the latter resemble very closely the 

 flower-heads of the grass. 



PUPA. The pupa is uniformly black, with a prominent headpiece 

 projecting beyond the prothorax ; the thorax and the 1st and 2nd 



