358 J. T. PATTERSON. 



roadside or barren spots, carry a higher percentage of galls than 

 do those which are located in protected regions. Likewise, 

 the moth larvae from the galls of the former are more highly 

 parasitized. 



SUMMARY. 



1. Copidosoma gelechiae, which is a parasite in the Solidago 

 Gall Moth, Gnorimo schema salinaris, has but one generation a 

 year. 



2. The egg of this parasite is probably laid during the month 

 of May. 



3. The type of development in Copidosoma is polyembryonic. 

 The number of individuals average about 191 per brood. 



4. In the youngest stages secured the process of division of the 

 egg into embryonic primordia is already in progress. The young 

 polygerm consists of two distinct regions: (i) An outer zone, or 

 nucleated membrane, containing the free polar . nuclei; (2) a 

 central region, containing the true embryonic nuclei. 



5. The embryonic nuclei segregate into groups, which become 

 surrounded by a dense layer of granular protoplasm and form 

 the primordia of the multiple embryos. 



6. During early growth the polygerm elongates into a cylin- 

 drical-shaped structure, which becomes broken up into several 

 spherical, primary masses by the formation of constrictions in 

 the nucleated membrane. Each primary mass receives several 

 of the primitive embryos. 



7. The primary masses become broken up into secondary 

 masses by further constrictions of the nucleated membrane. At 

 the end of these divisions, each embryo is separated from the 

 others and is surrounded by an inner and an outer involucre 

 the former derived from the granular protoplasm and the latter 

 from a portion of the nucleated membrane. 



8. The interstices between these masses become filled with an 

 inter-embryonal substance derived from at least three sources: 

 elements from the nucleated membrane, leucocytes, and cells 

 from the adipose tissue, which usually is laid down in the form 

 of a thick layer on the outer surface of the polygerm. The 

 entire structure thus becomes a complex, which may be called the 

 polygermal mass. 



