THE EMBRYOLOGY OF EUVANESSA ANTIOPA. 95 



with the course of these same isotherms. Yet each set of lines, those of 

 the faunal areas and of the isotherms, was worked out independently of 

 the other, and their somewhat remarkable agreement and yet failure to 

 correspond in many points is a very striking fact. Many more observa- 

 tions upon the distribution of insects within this belt and in its vicinity are 

 necessary before we can arrive at any satisfactory results, and construct a 

 map with a proper degree of accuracy : but the present attempt shows 

 very clearly that it is within the limits of New England itself that the 

 greatest progress in our knowledge is to be looked for, and that upon New 

 England naturalists devolves the duty of solving these zoo-geographical 

 problems. 



IV. 



STUDIES ON THE EMBRYOLOGICAL DEVELOPMENT 

 OF EUVANESSA ANTIOPA.* 



BY CHARLES W. WOOD WORTH, M. S. 



There is a wondrous workshop here, 

 E'eii in this daintj' little pod, 

 Here that mysterious workman, Life, 

 Builds matchless temples to his God. 



Embryology deals with all the phenomena of growth from the first 

 beginnings of life until its close ; therefore on account of the extent of the 

 subject the present paper is necessarily somewhat fragmentary in its char- 

 acter. In order to make it as compact as possible we will confine our- 

 selves to some of the earlier stages of development where some of the most 

 interesting problems in the whole domain of science present themselves for 

 solution. Embryology may be called the science of development. It 

 treats of life in motion and in this respect differs from Histology which is 

 essentially a "study in still life." It differs from Physiology by confining 

 itself to a single function of living; matter, growth. 



*The material used in the preparation of carmine and Czocher's cochineal. The latter is 

 this article consists of a small lot of eggs col- especially good; it is prepared as follows: 

 lected by Mr. Scudder and partly prepared by Place Ig. each of cochineal and burnt alum 

 Mr. Houghton, another and larger lot taken in a mortar and reduce to a powder; add 

 hy Dr. Dimmock and a third collected by my- lOOcc. of distilled water and boil until there 

 self near Fabyan's, "White Mountains; also is but 60cc., cool and filter; a few drops of car- 

 some specimens of the imago, part obtained by bolic acid should be added as a preservative, 

 myself and part sent me by Mr. Scudder. The hardness of the egg shell makes the 



The method of preparation which seems to egg very difficult to section, but if removed 



have given the best results is to kill by heating it is so delicate as to be almost certain to go 



in water at 80° C. which fixes the tissues very to pieces during the further manipulations, 



well. Eggs must now be punctured witli The parafin method of imbedding was em- 



a sharp needle; this is essentialin order that ployed, and the sections cut on the rocking 



the reagents used may penetrate. The most microtome made by the Cambridge Instru- 



satisfactory stains were Grenacher's borax ment Co. 



