( 328 ) 



which is widely separated from the jieuis-sheath (Ph XXIX. f, 38. 39. 44) ; the 

 latter with one or two teeth. 



? . Middle segments of antenna higher than long. A ridge in front of the 

 vaginal cavity strongly chitinised, niosially sinnate or cleft (PL XV. f. 18. 19). 



Larva and pupa essentially as in Sphin.r. — Food : Primus and other trees. 



liah. Nearctic liegion east of tiie Mississippi basin, in Canada extending further 

 west. 



The alidnmen is said hy Fernald, from whom Grote and Smith have copied the 

 statement, to be withont sjnnnles ; in this the Professor was wrong (see above nnder 

 Sphinx^, the abdomen agreeing in spinnlation with that of Sphinx. 



We have not seen a specimen of any of the three si)ecies of this genus iu 

 which there was an indication of more than one blue spot in the eye-patch of the 

 hindwing. The only spot jiresent varies in size and position. With which of the 

 three original spots is it homologous ? Does it corresjiond to the first, second, or 

 third spot of the species of -Sjo/Hwa; ? We find among Sph. jamaicensis specimens 

 with only one central blue spot: is this the same as the spot of Calasi/mbolusf 

 A comparison of the various species reveals the true homology. The three grey 

 lines of Sph. kindermanni, separated by black scaling, which re|iresent the more 

 ancestral form of the eye-patch, are pale blue in Sph. cerisi/i .mliccti and remain 

 separate ; the second and third become arched, join each other in front, and form 

 a more and more complete ring in the other subspecies of cerigyi, the first spot 

 disajipearing at the same time more or less. In ocellata, which is very closely 

 allied to cerisi/i, the ring is always complete and the first spot has entirely dis- 

 appeared. The same is the case in planus. If we bear this in mind and 

 compare now the hybrid astijlus x ocellata we observe at once that the ring of 

 this hybrid consists of the spot oi' asf>/lu.s and the outer jiart of the ring of ocellata, 

 which partis the thin/ spot of ccrini/i saliceti ; therefore the spot of ft*7///;^*' must 

 either be the second or the first spot of salt ccti, i.e., tlie sjiot of CaUmytnbolus is not 

 tlie spot of Sph. jnmaiccnsis f. ab. jamaicensis (see above), the blind eye of this 

 jamniccn.v's and oC Calasi/miolus are not homologous in respect to their pupil. 

 Further, if the Calaxi/niholiis jiupil were tlie first spot of saliceti, in the union 

 astijlus X ocellata all three spots would be present and should be represented at 

 least by some blue scales in the offspring of such a union. This is not the case in 

 the hybrids examined, and we conclude, tlierefore, that the ]inpil oi' a ■•<t>/lus (and the 

 other Cahisi/iiibolus) is homologous to I he jiroximal part of tlie ring of occllafa, i.e., to 

 the second spot or line of kindermanni and ce.risyi saliceti, as explained above. 



It would be very interesting to have the results of forced breeding on the lines 

 of Prof. tStandfuss's experiments. Such researches would doubtless result in the 

 production of individuals of Calasi/mlwlus with more than one blue spot in the 

 eye-patch. 



Key to the species : 



a. Fore- and hindwing scalloped . . . 274. C. crcnccata. 

 Fore- and hindwing not scalloped . . . . b. 



b. Distal margin of forevving distinctly angnlated 



at M', three distinct brownish lines with 

 grey interspaces ..... 270. C. myops. 

 Distill margin of forevving not distinctly 

 angnlated at M' ; the discal lines quite 

 indistinct, except at costal margin . . 27G. C. a.sli/lus. 



