216 



PSYCHE. 



[February iSg2. 



swarms just as some years ago I saw 

 Harma caenis in the Ogov6 region. 

 They seemed to come from nowhere in 

 particular, they flew in no order, no 

 two even keeping company. Some- 

 times only a dozen were visible, at 

 other times hundreds seemed to fill the 

 air. They flew a little E. of N. E. 

 This has no particular significance, 

 however, as this is the general direction 

 of the coast here. Even upon the beach 

 the migratory movement was easily ob- 

 served, and as far as I went back, (about 

 half a mile) the air seemed full of the 

 flies. None were returning, and all 

 flew as if they had a definite purpose in 

 view. A native remarked it, and ven- 

 tured, in calling my attention to the 

 movement to add 'Sometimes they fly 

 so, and sometimes they fly in the oppo- 

 site direction.' "... 



"I am utterly at a loss to account for 

 the phenomenon. The explanation 

 which I suggested for the migration of 

 Harma caenis, which this exactly re- 

 sembles, will not apply here. That 

 took place near the end of the dry sea- 

 son and was toward the approaching 

 rains. But here the rains are frequent 



now, and if these flies are seeking any- 

 thing to northward it must be dry 

 weather." 



Chrysopsyche mirifica Butler. 



I have received from Mr. Good sev- 

 eral specimens of this exceedingly beau- 

 tiful bombycid, and also a specimen of 

 the cocoon, which is very tough and 

 dark chocolate brown in color and 

 studded all over as are many of the 

 cocoons of the African Bombycidae 

 with minute spines, which are derived 

 from the epidermis of the caterpillar. 

 The figure upon Plate 5 will serve 

 better than a description to give an idea 

 of the form of the cocoon. 



EXPLANATION OF PLATE 5. 



Fig. 1. Chrysalis of Saturnia arnobia 

 Westw. 



Fig. 2. Chrysalis of Idiomorphus vala 

 Ploetz. (lateral view). 



Fig. 3. Chrysalis of Idiomorphus vala 

 Ploetz. (dorsal aspect) . 



Fig. 4. Larva of Harma caenis Drury. 



Fig. 5. Chrysalis of " 



Fig. 6. Cocoon of Chrysopsyche miri- 

 fica Butler. 



CONCERNING THE "BLOOD-TISSUE" OF THE INSECTA.— I. 



BY WILLIAM MORTON WHEELER, WORCESTER, MASS. 



Hitherto little attention has been de- 

 voted to the study of the blood, fat-body, 

 and allied structures in insects. We 

 have extensive monographs on the eyes 

 and other sense-organs, on the muscu- 



lature and nervous system, and even on 

 the alimentary tract and its various sub- 

 divisions, but few serious attempts have 

 been made to fill the gaps in our knowl- 

 edge of the physiologically highly im- 



