STRUCTURAL PARALLELISM BETWEEN 
SPORE-FORMS IN THE ASCO- 
MYCETES^ 
C. R. Orton 
(With Plate 152, Containing 7 Figures) 
The term “ structural parallelism ” is here substituted for the 
word “ homology ” which was used when the paper was first pre- 
sented. There was some objection to the use of the word homol- 
ogy and with good reason, for although Brefeld appears to have 
used the word in a somewhat similar manner, the general use of 
this conception has been, especially in zoology, not a structural or 
functional resemblance but a phylogenetic similarity of origin. 
The similarity which the writer wished to bring out in this paper 
might be more nearly expressed by the word analogy but this im- 
plies a functional similarity which, although it may be present, 
is not precisely what is in mind. 
The term physiological parallelism was suggested as the general 
one used to describe similarities like those enumerated in this 
paper. It seems, however, that even this expression is not strictly 
appropriate, for the word physiological implies again a functional 
relationship. 
The relationship which the writer has in mind is one of a purely 
structural nature between ascospores and conidia in certain spe- 
cies of Ascomycetes, though similarity in color often accompanies 
it. Considering the subject purely from this standpoint, the term 
structural parallelism would seem to fit more closely the phenom- 
enon which the writer desires to express in this paper. This ap- 
pears to be the first time that a study has brought facts of this 
sort together for this class of fungi, although such a relation un- 
doubtedly has been observed by other investigators. 
We are indebted to Tulasne for the early researches among the 
1 Read before the Botanical Society of -\merica at the Atlanta Meeting, 
December 31, 1913. (Abstract. Science 39; 258. 1914.) Contribution from 
The Department of Botany, Pennsylvania State College. No. 2. 
21 
