104 GEO. 8. HUNTINGTON 
drawn by the French observer on the cases of human bronchial 
variations reported by Chiari (6, 7, 8, 9) and Dalla Rosa (10) 
with double right eparterial bronchi, in which the additional 
bronchus arose either from the stembronchus or trachea. Narath 
suggested that analogous variants, if they developed on the left 
side, would sufficiently account for d’Hardiviller’s ‘left eparterial 
vesicles.’ He further cited two instances in the adult rabbit in 
which the upper lobe of the left lung, normally supplied by the 
ascending branch of the first ventral hyparterial bronchus, re- 
ceived an additional branch arising from the stembronchus nearer 
to the tracheal bifurcation and dorsal to the pulmonary artery, 
thus repeating in atypical adults the temporary conditions de- 
seribed by d’Hardiviller for the normal embryo. 
In a series of 70 adult rabbit lungs, which I examined by cor- 
rosion for the occurrence of bronchial and arterial variants, I 
found in one individual the cranial pole of the left lung supplied 
by an atypical first branch of the left stembronchus arising dorsal 
to the pulmonary artery, and corresponding in position to the 
larger eparterial bronchus of the right lung. I have examined 
with the utmost care all the series of rabbit embryos of the criti- 
cal stages, between 12 and 15 days, and from 8 to 11 mm. in 
length, which were available to me. These include the series of 
the Columbia collection and a number of preparations lent by 
my colleagues in other institutions. Not in a single instance 
has it been possible to detect even an approach to the condi- 
tions described by d’Hardiviller. A very large and closely graded 
series of cat embryos in the Columbia University Collection, 
with numerous individuals of the same stage, and a similar, 
though less extensive series of embryos of the albino rat, which 
I owe to the liberality of The Wistar Institute, have given the 
same negative results. I do not believe it possible that these 
preparations can fail in representing correctly the true morpho- 
logical conditions obtaining in the critical stages of these mamma- 
lian embryos, and I hence do not hesitate to pronounce d’Hardi- 
viller’s conclusions erroneous and his generalization unwarranted 
on the evidence. D’Hardiviller does not mention the number of 
embryos in which he found his evanescent vesicle. The context 
