Myers. — Life-history of some New Zealand Insects. 237 



The first instar only is white or colourless, except for a bright yellow 

 area surrounding the orifice of the scent-gland, and caused by the appear- 

 ance of that gland showing through the transparent exoskeleton. The 

 head is smooth and shining, while the rest of the dorsal surface appears dull. 



In October and November the first ecdysis occurs after about six days. 

 The cuticle splits along the mid-dorsal line of the thorax. The second 

 instar shows little structural change ; but colour appears as a dark grey 

 on the head, two grey streaks separated by a narrow pale line along the 

 whole dorsal surface, and dark spots on the lateral edges of each segment. 

 The scent-gland opens on a raised area of a dark colour. The individuals 

 of the first and second instars show a habit of standing remarkably high 

 on their legs, a peculiarity noted by Kershaw and Kirkaldy in an Oriental 

 species. 



The subsequent nymphal history is marked by an enormous increase in 

 the size of the body relatively to the length of the appendages ; by the 

 appearance of spines on the lateral margins of the head ; by the growth 

 of tubercles and spots on the posterior margins of the abdominal segments ; 

 by the increase of granulation over the whole dorsal surface ; and, above 

 al^ by the gradual curving of the mesonotal and metanotal posterior 

 margins with the formation of wing-pads, of which those of the meso- 

 thorax, forming the rudimentary tegmina, soon cover entirely those of the 

 metathorax. The compound eyes of the second and subsequent instars 

 are brilliant red. 



Although Osborn considers five instars to be the normal number in the 

 Hemiptera, Kershaw and Kirkaldy note eight in the case of Dindymus 

 sanguineus Fabr., an Oriental Pyrrohocorid ; and there is every indication 

 that Ctenoneurus hochstelteri passes through an equally large number of 

 stadia. The difficulty of ascertaining the exact number of instars may be 

 increased by individual as well as seasonal variation. Such a variation, 

 according to Tillyard, is well known to occur in certain dragon-flies, where 

 the nymphal instars are extremely numerous. 



Maternal Solicitude. — Although J. H. Fabre has cast the weight of his 

 authority against the classic example of De Geer's " grey bugs " (Elasmucha 

 grisea) and their display of parental affection, it may be of interest to note 

 that imagines of C. hochstetteri are sometimes found carrying several first 

 or second instar nymphs on their backs and sides in a manner comparable 

 to that of Lycosid spiders. Considering the gregarious habit of the species, 

 perhaps we should rule out maternal solicitude as an explanation ; but it 

 is significant that these young nymphs do not apparently cling to older 

 nymphs which closely approach imagines in size. 



References. 



1. J. C. W. Kershaw and G. W. Kirkalky, On the Metamorphoses of Two 



Hemiptera-Heteroptera from South China, Ent. Trans., p. 59, 1908. 



2. Biological Notes on Oriental Hemiptera, No. 1, Jour. Bombay Nat. Hist. Soc, 



p. 596, 1908. 



3. G. W. Kirkaldy, On the Interesting Nature of Heteropterous Metamorphoses, 



The Entomologist, p. 58, 1908. 



4. Upon Maternal Solicitude in the Hemiptera, &c., The Entomologist, pp. 113-20, 



1903. 



5. H. Osborx, The Meadow-plant Bug (Miris dolabratv.s), Jour. Ag. Res., vol. 15, 



No. 3, 1918. 



