290 Mr. Poulton's notes in 1886 



shape of the horn suggests Sphinx, just as its surface 

 suggests the closely allied genus Acherontia. There are 

 six oblique white stripes on the sides, with distinct 

 anterior borders formed of darkened ground colour, 

 while the borders are faintly continued on to the dorsal 

 area, and above the subdorsal tend to meet in a series 

 of Vs. This latter suggestion of the first and " eighth 

 stripe " is also present in the normal position, and the 

 whole arrangement almost exactly recalls that of 

 Smerinthus and the early stages of Sphinx ligustri. Thus 

 the seventh stripe is especially prominent, and runs up 

 into the base of the caudal horn, while the posterior 

 part of the subdorsal is continuous with the stripe, 

 exactly as in the above-mentioned genera. This remark- 

 able union of characteristics of such different genera 

 serves to indicate the morphological identity of the faint 

 oblique stripes of Chcerocampa elpenor and of C. porcellns 

 with the more distinct markings of Smerinthus and 

 Sphinx, and I have little doubt that these features will 

 be found to exist in the younger stages of Chcerocampa, 

 when they are examined with this object in view. The 

 last character is an extremely ancestral feature, — the 

 permanence of the dorsal tubercles which I have de- 

 scribed in the younger stages of Sphinx and Smerinthus. 

 These persist as two pairs of white marks upon the 

 dorsal surface of the abdominal segments in front of the 

 eighth ; white spots also occur on the dorsal surface of 

 the thoracic segments. Traces of at least one of the 

 two lateral tubercles can also be faintly made out as an 

 especially white part of each stripe above and rather 

 behind the spiracle. Since my description of these 

 tubercles in young Sphinx larvse a paper has appeared 

 by Dr. Wilhelm Miiller (" Siidamerikanische Nymphali- 

 denraupen," ' Zoologischen Jahrbiichern,' J. W. Spengel. 

 Jena, 1886), in which he describes the same tubercles 

 in larvse of many widely-separated groups, and calls 

 them the " primitive tubercles." Before I read his 

 paper I had also recognised them in many different 

 larvae, and had regarded them as very primitive features. 

 In fact, I had discussed with Prof. Meldola my intention 

 to work out these characters, which are common to 

 widely-separated larvse, and from them to endeavour to 

 reconstruct, as far as possible, their arrangement in the 

 ancestral larva. Dr. W. Miiller has, however, now 



