Watt. — Study of New Zealand Entomology. 24.") 



Art. XXVIII. — Contributions to the Study of New Zealand Entomology, 

 from an Economical and Biological Standpoint : No. 1 — Plusia chalcites 

 Esp. ; No. 2 — Nyctemera annulata Boisd. ; No. 3 — Venusia verriculata 

 Feld. (Lepidoptera). 



By Morris X. Watt, F.E.S. 



[Read before the Wanganui Philosophical Society, 23rd November, 1914.] 



Introduction. 



It is my aim in these and future contributions to bring together as complete 

 a knowledge of each species as is possible. It is of great economic 

 importance that we should know the range or distribution and full par- 

 ticulars of the habits of our native insects. The life-histories may at first 

 sight appear too elaborate, but they are the minimum demanded by the 

 present-day biologist in his researches on the relationship and classification 

 of the Lepidoptera and other families. My excuse is that science demands 

 that these details should be known. The bibliographical and synonymic 

 lists appended to each species are as complete as it has been possible to 

 make them. All the more important information gleaned from these has 

 been made use of in the contributions, but where it would have been 

 necessary to make long extracts reference to the original work has been 

 made in the text. I should like to gratefully tender my sincerest thanks 

 to Mr. W. G. Howes, of Dunedin, and Mr. G. V. Hudson, of Wellington, for 

 the kindly help they have given me. 



The following keys for the description of the ovum, larva, and pupa 

 in the Lepidoptera, showing the minimum of information required, are 

 useful to workers who desire to further our knowledge in this branch. 

 The bibliography below, though not exhaustive, includes works known to 

 the author to be of real assistance to any desiring a sound working know- 

 ledge of the subject. 



For describing ova : — ■ 



(1.) Class (flat or upright). 



(2.) Shape (if necessary, transverse and longitudinal sections). 

 (3.) Dimensions (length, breadth, height). 

 (4.) Sculpture (smooth, cellular, or otherwise). 

 (5.) Micropyle (arrangement, number, and size of cells). 

 (6.) Shell (strong, glossy, transparent, smooth, or otherwise). 

 (7.) Colour (at laying and subsequent changes). 

 (8.) Period of incubation; dates of hatching, &c; manner of laying; 

 other notes of interest. 

 For describing larvae, the following details should at least be included 

 for each stage — -i.e., after each successive moult (Tutt, " Hints for the 

 Field Lepidopterist," pt. iii) : — 



(1.) Colour and markings; detailed measurements of head, thoracic 

 and abdominal segments ; appearance of same ; the position 

 of a lateral flange, swellings, &c. ; the number and position 

 of prolegs. 

 (2.) The number of subsegments to each segment, and the variation 

 in their character on different segments. 



