MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 33 



It appears from Lt. Col. .1. W. Faucett"s description aiul ti>>iire of thi; larva of Protupan-e 

 wauritii Butler, of South Africa, that there are "paired iiunips on first and second soiiiites." 

 Judging by his figure, these humps are lower, more rounded, ])ut ai-e situated on the front edge 

 of each segment, as in Ceratoniia. We thus have in two quite difl'erent genera of Sphinginie this 

 singular mimicr}- of the tlioracic tubercles of Ceratocampina\ 



The jir»t larval stage of V'jratomia undulosa. — (PI. XXXIV, fig. 5.) Stage I. The larva is 

 long, slender, cylindrical, but widely differs from that of C. ainijntur in the same period of life 

 in being destitute of the four boss-like rudimentary horns, the .segments being in this respect 

 normal. The hinder or fourth pair of mid-abdominal legs are, judging liy ^Ir. Joutel's drawing, 

 even smaller than the third pair, which are much larger than those in front. The bodj' is of an 

 uniform pale whitish fiesh color, with no markings. 



Incongruence in the genus Ceratomia. — Ceratoniia unduhisa seems to be generically distinct 

 fi-om C. amyntor in stage I, both as regards the absence of the rudiments of dorsal false horns 

 and in the mid-abdominal legs Ijeing smaller than the others, or at least no larger than those of 

 the second pair. 



The larva of (', ratal j)ie in all its stages, as described and figured by Kiley. is also entirely 

 unlike C. amyntor, being, after the first molt, smooth bodied, while its markings are very 

 diflerent, the body being without anv oblique whitish lines, and in the two last stages the skin is 

 "smooth and velvety," In the second stage the head is smooth and polished, with no traces 

 whatever of thoracic false horns (Rep. U. S. Entomologist, 1SS3, p. 189). 



The larva of C. hagenl resembles, according to Riley, that of C. undu/om; it is marked with 

 oblique yellowish-green lines. The incongruence between the larvas of the species now referred 

 to Ceratomia, is striking. It is to be observed that Riley refused to associate either 

 C. catcdpx or C. hagenl with C. amyntor, but referred them to Sphinx. Certainly C. amyntor 

 stands alone, and the pupa^ and imagoes of the genus Ceratoniia as now acce^ited should be 

 revised. 



VIII. PHYLOGENY OF THE CERATOCAMPINyE. 



The most primitive, generalized genus of the group is Adelocephala. unless it should be 

 found that AstyJls hellatrix is still more so. Unfortunately the larva and imago of this form are 

 not obtainable. 



That Adelocephala is the stem-form from which the other genera have originated is 

 suggested by the larval armature, the presence in the undetermined lirazilian larva (PI. XLIX, 

 fig. i) of quite well developed protluracic horns, and bv the equality in length and shape of the 

 dorsal horns both of the thoracic and abdominal segments. 



Already in Syssphinx the armature has undergone a very considerable I'eduction, showing 

 that it has diverged from the main line of descent. 



A decidedly remote side branch, with no annectant foi-m, is Anisota, which notablv ditiVrs 

 from all the rest of the group in the reversion of the caudal horn to a pair of separate setiferous 

 tubercles. This would .seem to be the result of a per saltum retrograde mutation — a case of 

 reversional evolution; also the decided reduction in length of all the thoracic horns, except those 

 of the second thoracic segment, is a case of discontinuous evolution by partial atrophy. Corre- 

 lated with these modifications are certain difierences in habits in tiie case of the species of 

 Anisota, which are gregarious and seem to be avoided by birds, judging by their feeding in 

 exposed situations and by tiie great luimber of individuals. 



Returning to the main evolutional path of the group, we observe that Eacles is not I'emoteiy 

 disconnected from Adelocephala, although in this genus towai'd the end of larval life, in contrast 

 with the exuberant growth of horns in the earliest stage, there is a reduction in the length of 

 the spines. The pupa is of the type of that of Adelocephala, and in the imago there is not a 

 great difl'erence. 



