26 Psyche [April-June 



placed in the family Ithoniidse, judging from the nature of its 

 thoracic sclerites, head capsule, and other features, although this 

 has not yet been done in any grouping of the Neuroptera which I 

 have seen thus far). In fact, it is very probable that the ithoniids 

 are quite like the forms which gave rise to the lines of descent of 

 the Lepidoptera and Trichoptera, though Tillyard and Handlirsch 

 seem to think that the Mecoptera (or their fossil relatives) repre- 

 sent the ancestors of these two groups. The galeae of the maxillae 

 (see structures labeled "mx" in Fig. 4, of the micropterygid) are 

 not developed in the Trichopteron shown in Fig. 2, but Ulmer, 

 1905 (Zool. Anz. 28, p. 56) and Cummings, 1913 (Ann. Nat. Hist. 

 XI, p. 308) describe the maxillae of the Trichopteron Dipseudo'psis 

 having the parts well developed, and with the galeae^ as long as 

 those of Mnemonica ("mx" of Fig. 4). The pupa of Mnemonica 

 (Fig. 9) has huge crossing mandibles suggestive of the type found 

 in Trichoptera (Fig. 7), but I have not found any Trichoptera in 

 which the mandibles are enlarged at the tips as in Mnemonica, nor 

 liave any of the trichopterous pupae which I have examined, a 

 frontal process like that labeled "e" in Fig. 9 of the pupa of 

 Mnemonica. 



The lateral region of the thorax of Mnemonica (Fig. 1) is aston- 

 ishingly like that of the Trichopteron (shown in Fig. 3), the out- 

 lines of the upper and lower divisions of the mesothoracic epister- 

 num ("aes2" and "kes2") being very similar in both instances. 

 It may be remarked in passing, that the region labeled "aes" is 

 710^ the entire episternum, nor is the region labeled "kes" the 

 trochantin (which is labeled "tn" in both figures) as is usually 

 stated to be the case, and the hinder portions of the coxae labeled 

 "me" are not detached portions of the epimeron "em," which 

 have become adherent to the coxae — but these features have been 

 thoroughly discussed in an article dealing with the basal segments 

 of the leg in insects (Zool. Jahrb. x\bt. Anat., 39, p. 1) and need 

 not be gone into further here. 



As is true of all Lepidoptera which I have examined, the meso- 

 thoracic merocoxa "me2 ' (Fig. 1) or posterior division of the coxa 

 extends along the entire 'posterior border of the anterior coxal 

 division "VC2" in Mnemonica (Fig. 1), and there is no " basicoxite" 



'The proboscis of Plectrotarsus is not "coiled," as was formerly stated to be the case, but is 

 merely folded. 



