93 



Between the 8Coli we see in instar II small setae. In instar 7 

 no t«pot8, but in instar II we find spots along the front and 

 back edges of the segments, they are connected with each other 

 by a line above the stigma. T^ater on they are irregular. 



Family Sphingidae. 



Weismann's important study (1876) has been mentioned before 

 in detail. Chapter II, p. G sqq. 



Mkldola translated this work in 1882 and drew attention to the 

 resemblance with the flagellate organ Papilio and Dicranura possess. 



W. MOller (1886, p. 250) relates among other things that 

 the horn is composed of the two primary hairs 1 = Ds. of tlie 

 8th abdominal segment and gives a drawing of it. 



Poi'LTON (1884, 1888, 1890) gave his attention to the colours 

 of the pupae which agree with those of the caterpillars. He thinks 

 that the horn arises from two tubercula. I intend to discuss 

 Poi'LTOx's opinion on the colours in the chapter on pupae. 



Dr. Jur. M. C. Piepers published in 1889 a treatise in Dutch 

 and in a more extensive form in German in 1897. Piepers, who lived 

 for many years in the Dutch East-Indies, raised numerous Sphin- 

 gidae from the e^^. He found that the horn is very movable. 

 [J. Th. OrDEMANs discovered the particular muscles which cause 

 this movement]. Then he discusses the hypothesis of Th. Goossens 

 (1873) who thought that the horn serves to protect the glands 

 by which the urine is secreted. Piepers thinks it is used to 

 drive away the Ichneumonidae and Tachinhiae. The granulation is 

 the consequence of a secondary disappearance of prickles so that 

 the organ may have been a poisonous prickle formerly. 



Piepers found also that in the beginning the horn possesses 

 two points. 



Packard (1890, p. 513) is remarkably short in treating this 

 organ, but in 1905 he discusses it at length. With it he draws 

 figures of Ceteromia amyntor. His PI. XXXIV and XLII agree 

 almost entirely with mine of Sphinx Ugustri, in so far as there 

 are no secondary setae except on the horn, and with Smerinthiis 



