125] LEPIDOPTEROUS LARVAE — FR ACKER 125 



ing a great part of each segment unprotected. In io the entire body 

 surface seems to be covered. 



Coloradia pandora was seen only in the early larval stages, when 

 the scoli are long and sparsely branched. These may possibly become 

 reduced in the mature larva. Between and slightly behind scoli Rho and 

 alpha on the abdomen is a single seta, beta. 



Basilona imperialis. The larva of the yellow imperial moth is well 

 known ; the long setae enable it to be identified at a glance. 



Citheronia. The caterpillar of C. regalis is commonly known as the 

 "Hickory Horned Devil", the horns being the subdorsal scoli of the 

 meso- and metathorax. In this species each of these segments is armed 

 with a pair of very long scoli on each side while in C. sepulchral/is but 

 one long scolus is found on each side on each of the two segments ; in 

 other words the former species has scoli Rho very well developed on the 

 thorax, while in the latter scolus Rho is no larger than Kappa or Pi. 



Adelocephala. The one species of this genus, A. bicolor, is very 

 similar to Syssphinx in the larval stage, but the reduced armature on 

 each alternate abdominal segment and the echinulate mesothoracic 

 scoli serve to separate them. 



Syssphinx. Peculiar smooth processes, similar to the thorns of a 

 rose, take the place of scoli in S. heiligbrodti, the only species I have 

 examined, and make it recognizable at a glance. Even the thoracic 

 scoli are nearly smooth. As the genus is distinct from other Saturnians 

 in adult characters, it is probable that these processes occur in the other 

 two American species, S. bisecta and S. quadrilineata. 



Anisota. While the species of Anisota are very common, their small 

 size and plain appearance have caused them to attract less attention 

 than their relatives. They may be easily distinguished from each other 

 as follows: 



a. Scoli alpha of abdominal segments 1 to 6 very much reduced and 

 inconspicuous ; scoli Kappa well developed ; caudal projections of 

 suranal plate scarcely longer than lateral processes. A. rubicunda 

 aa. Scoli alpha of abdominal segments 1 to 6 subequal to Kappa in size. 

 b. Scoli alpha of abdominal segments 1 to 6 much shorter than thor- 

 acic legs. 

 c. Caudal projections of suranal plate distinctly longer than wide, 

 pointing directly caudad ; body with conspicuous black longi- 

 tudinal stripes, not dotted. A. sanatoria 

 ce. Caudal projections of suranal plate about as long as base is 

 wide, pointing caudodorsad ; body without black stripes but 

 covered with minute dots. A. virginiensis 



