13 



laying of a species, where, at what time of day, in large or small 

 batches, whether naked or covered, whether protected or exposed. 

 How long does the egg "stage last ? and what is the relation between 

 this and the habit of deposition ? Are the eggs numerous or few ; 

 and what are the sizes of the batches ; or are the ova laid singly ? 

 What changes take place with the fertile eggs which are or are not to 

 be observed when the ova are infertile? The sizes of the ova should 

 be very carefully measured, and to all photographs should be 

 appended the magnification. 



Turning to the consideration of the larvae, Mr. Tutt called atten- 

 tion to the generally cylindrical shape, the segmentation, the regional 

 division into head, thorax and abdomen, etc. He then stated at 

 some length what has now become of far more importance than these, 

 viz. the position, numbers and character of the tubercles that bear 

 setaa or hairs, and which are found on certain well-defined areas of 

 the body. He described their position on the various segments, 

 their absence or presence at different instars, their varying position 

 in the different groups, and their various peculiarities and modifica- 

 tions ; at the same time his remarks were illustrated by numerous 

 diagrams very kindly prepared and lent him by Mr. Bacot. The 

 special nomenclature of these tubercles was as follows : Tubercle i 

 (the two front ones on the dorsum of each segment) ; Tubercle ii 

 (the two hinder ones on the dorsum) ; Tubercle iii (above each of 

 the spiracles) ; Tubercles iv and v (just below the spiracles, but 

 often moved to neighbouring positions) ; Tubercle vi (between iv 

 and v) ; and Tubercle vii (on the upper outside margin of the 

 legs). These are known respectively as : (i) anterior trapezoidals ; 

 (ii) posterior trapezoidals; (iii) supra-spiraculars ; (iv and v), sub- 

 spiraculars (v sometimes becoming pre-spiracular, and iv becoming 

 post-spiracular) ; (vi) laterals ; and (vii) marginals. 



Besides all the usual statements as to colour, markings, detailed 

 measurements and appearances of head and various segments, the 

 number of sub-segments and their characters and appendages, the 

 number and position of the prolegs, etc., there should also be noted — 

 the position of the spiracles, the character, arrangement, and complete- 

 ness of the hooks on the prolegs, the structure of the primary and 

 secondary setre and their variation in number, position and develop- 

 ment, the presence of any secondary tubercles, and whether any hairs 

 are present not connected with the definite tubercular structures. 



It was necessary to note all these points at the successive instars, 

 "and particularly was it all-important to most carefully make a detailed 

 description of the newly-hatched larvce, for often such records were 

 found to be of immense value for classificational purposes, when per- 

 haps details at any other instar may be of comparatively little value. 



For fuller details see Dyar, " A Classification of Lepidopterous 

 Larvae," Ann. New York Acad. Sci. viii, p. i8 ; Tutt, " Nat. Hist, of 

 Brit. Lep.," i, pp. 6-54 ; viii, pp. 1-22 ; " Hints on Collecting 

 Lepidoptera," pt. in, pp. 3-32 (1905). 



