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RICHAHD ASSHETON. 
my Grymnarchus paper in the ‘ Budgett Memorial Volume ’ ; 
and although it is doubtless a “ wild and hypothetical specu- 
lation,” yet it seems to me to be au idea which deserves 
consideration by both embryologists and palaeontologists. It 
is curious, however, that the reasons which led me to the 
idea are quite different from those which brought Professor 
Ilubrecht to the same conclusion (' Budgett Mem. Vol.,’ p. 
407). 
And although I was well aware of, and alluded to, the 
close resemblance between the trophobhist of Eutherian 
mammals and the Deckschicht of Teleosteans (“Report of 
Eggs and Larvae from the Glambia River,” ‘ Budgett Mem. 
Vol.,' pp. 434-6), it never struck me to regard this as 
evidence of affinity between the groups ; and I cannot yet 
get over the difficulties of regarding these and the other 
outer layers discussed in the preceding pages as homologous, 
for the difficulties apiDear to me insurmountable. 
In conclusion, may I again express my appreciation and 
admiration of the great work upon which I have ventured 
to comment. And if, in my excursus, I have settled more 
often and dwelt longer upon points where I have found 
myself in opposition to the Professor, it has been in the 
belief that such disputations tend towards the elucidation of 
the truth, and not because I am in any way insensible of the 
magnitude of the work, nor because I am not to a large 
extent in accord with the conclusions based upon it ; for no 
one can realise more clearly than I do how much of the 
intei’est, which we who have the more recently been drawn 
to this field of research in mammalian embryology feel in 
the subject, is due to the brilliant researches and writings of 
Ilubrecht. 
List of Papers referred to in the Text. 
Assheton, R. (’91‘). — “ A Re-investigation into the Early Stages of the 
Development of the Rabbit,” ‘ Quart. Journ. Micr. Sci.,’ vol. 37. 
(’94-).—“ On the Phenomenon of the Fusion of the Epiblastic 
Layers in the Rabbit and in the Frog,” ‘ Quart. Journ. Micr. Sci.,' 
vol. 37. 
