28 



(1904, I.e. p. 423): „The moment of the hatching does not cor- 

 respond to an exact point of the embryonic evolution. This mo- 

 ment is of a purely physical nature and depends on the smaller 

 or larger quantity of nutritive reserves contained within the egg^\ 

 we may expect that in other families segment 12'^ will remain 

 independent till after the first instar. The more so as in 1896 

 Chapman was able to show so great a difference between the 

 eggs of Lepidoptera. 



Therefore we need not be surprised if some writers are con- 

 vinced that there are more than ten abdominal segments, and others 

 that there are only ten or less. 



For my part I think that it entirely depends on the specimens 

 examined. 



PouLTON (1890) says that „behind the 7tli abdominal segment 

 most writers only detect a somewhat confused mass of segments, 

 but a careful comparison with the pupa proves that it is certainly 

 made up of three segments." He arrived at this conclusion through 

 the homologizing of the setae and through Jackson's investi- 

 gations (in 1890) on the pupae, which harmonized with the older 

 (1875) observations of that writer on the so-called cremaster of 

 the pupae, proving it to be the same as the anal-flap of the 

 caterpillars. Poulton's conclusion is I.e. p. 195: „In the pupa, 

 this ninth abdominal segment, although small, is as distinct as 

 any of the others. The part behind this segment in the larva 

 forms a tenth abdominal segment. This segment is separated into 

 a dorsal portion (X') of which the posterior and lower part form 

 the anal-flap and a ventral portion (X), of which the anal claspers 

 form the posterior and lower part, between the latter is the anus". 

 On p. 196 he says that for a long time he has considered that 

 X consisted of two segments. 



Spuler (1910) also believes he can discern a 14th segment, 

 fig. 4, p. XXVII. The last three segments he takes together as the 

 anal segments. They often bear an „After-klappe". „That the last 

 part should be looked upon as the dorsal part of a 14th ring, 

 consequently of the 11th abdominal segment, is proved by the 



