the; saddled prominent. 315 



The term "saddled" is suggested by the position of the most 

 conspicuous of the dorsal markings. In different designs this 

 saddle mark appears near the end of the second larval stage and 

 persists through the third, fourth, and fifth stages, that is, it is 

 present from the time the caterpillars are 8 or 9 days old until 

 they are full fed. The saddle mark occurs on the mid dorsal 

 portion of the third abdominal segment, and extends in most 

 cases over the fourth and on to the fifth. Like all the markings 

 in this species the saddle mark is subject to great variation and 

 is sometimes exceedingly faintly traced or absent in the fifth 

 iiistar. The saddle designs which accompany this discussion 

 are drawn from specimens in the third, fourth, and fifth instars 

 and represent only a few of the countless variations. 



We have among the slug caterpillars the "saddle-back cater- 

 pillar," Sibine stimulea Clem., but with the family name 

 Prominent retained there is certainly no danger of a confusion 

 between the names of these two exceedingly dissimilar species. 



The; Present Outbreak. 



About the middle of August, 1907, the Station mail was 

 flooded with complaints of this caterpillar which had made 

 startling inroads in certain localities.* Two of these localities 

 were visited immediately, — a large maple grove at South Leeds 

 and approximately 100 acres of beech growth at Upper Glouces- 

 ter being found at that time defoliated. The full fed cater- 

 pillars were observed to be vigorous and forming apparently 

 healthy pupae, so that a more serious attack was feared for the 

 present season. With this in view the last of May, 1908, the 

 writer made an initial trip into regions known to be infested 

 the previous August, and frequent trips for observation were 

 taken to certain of these localities from southwestern part of 

 Oxford county to the southern part of Piscataquis county, dur- 

 ing the entire caterpillar season. Insectary observations have 

 also been made on this species through the entire life cycle. 



While for the most part only enough attention could be paid 

 to this species to accumulate a miscellany of observations, the 

 work has resulted in some definite data not previously known for 

 this species. The fact that for Maine only one brood occurs, 

 the unbroken series of molting records for the same lot of cater- 



* Me. Agr. Exp. Sta. Bui. No. 148. Insect Notes- for 1907. 



