286 The American Naturalist. [March, 
EMBRYOLOGY.’ 
Sexually Produced Organisms without Maternal Charac- 
ters ?— When it was announced by Boveri’ than an organism might 
be formed from a fragment of an egg fertilized by sperm of another 
species and then possess only the characters of that latter paternal spe- 
cies, this fact naturally gave rise to much speculative application, and 
was welcomed as evidence of the great value to be set upon the nucleus 
in the processes of heredity. Boveri stated that bastard larve formed 
by sperm of Echinus microtuberculatus and eggs of Sphaerechinus 
granularis were in all respects middle forms between the species. He 
also stated that when the eggs of the latter species were shaken so that 
they broke and lost their nuclei and were then fertilized by the sperm 
of the former, dwarf larvz were formed that had the characters of the 
male parent, Echinus, only, and not those of the female parent, Spheer- 
echinus. Thus, he concluded, the male sperm nucleus transmitted 
paternal characters, while the egg protoplasm, deprived of its nucleus, 
gave none of the maternal characters to the offspring. 
Oswald Seeliger’ has repeated these experiments with the same spe- 
cies and has shown that Boveri’s conclusions are not the necessary ones 
to be drawn from the evidence, but only interpretations that ignore 
most weighty factors. 
In two plates he gives careful figures of the larve of both species at 
the same stages and also figures of the bastard larve. An examina- 
tion of these convinces one that the normal bastards, or those from 
whole eggs, are not by any means exactly intermediate between the 
two parents in all cases. Many do combine the parental characters in 
this way, but many are much like the father and others more like the 
mother. This holds both for the general shape and for the structure 
of the larval skeleton. 
Since then, many bastards from whole eggs resemble the father, 
there is no proof that the bastards from broken eggs were not also from 
nucleated pieces, for it must be borne in mind, that Boveri failed to get 
larvee from isolated fragments, and obtained his dwarf larve from the 
1 Edited by E. A. Andrews, Baltimore, Md., to whom abstracts, reviews and 
preliminary notes pmd be sent. 
? See American Naturalist, March 1, 1893. 
3 Roux Archiv. $ P EPAPER I, 2, Dec. 11, ’94. 
