SECTION IV, 1912 [61] Trans. R. S. C. 
On Some Organs in the Cervical Region of the Frog. 
By FLORENCE D. THOMPSON. 
Presented by PROFESSOR SWALE VINCENT. 
(Read May 16, 1912). 
The organs treated of in the present note include several bodies 
in the cervical region of the frog which are frequently confused one 
with another and of which no very full account has yet appeared, so 
far at any rate as their adult anatomy and histology are concerned. A 
fairly full account of some of these bodies is given by Gaupp in Ecker’s 
handbook’; but this author gives no histological drawings, and the only 
such drawing, so far as I am aware, of the ventral branchial body is the 
one previously given by myself.’ 
The plate representing semi-diagrammatically the general position 
of these bodies will, I hope, be found useful to teachers. 
Nothing need be said about methods of work. The methods 
employed for histological examination have been those most approved 
for the purposes of general microscopical work. Very few special 
cytological methods have been employed. 
1. THe Tuyrorp Bopy. 
A full account of the general anatomy is given by Gaupp.* 
The body is deeply placed and by no means easy to find without 
considerable practice. It seems also to be less easily visible in winter 
frogs than in summer frogs. The frog possesses two thyroid lobes 
separate from each other in the adult, though originally derived from a 
median unpaired rudiment. The gland of each side is an oval corpuscle, 
placed ventrally to the root of the processus postero-medialis of the 
hyoid cartilage and occupies a deep concealed position. (PI. I, fig. 
1, thyr.) It seems very probable that the ventral branchial body has 
often been mistaken for the thyroid. In the specimens I have examined, 
the thyroid has measured in its largest dimensions 1.5 mm. x 0.5 mm. 
(Pl. IL, fig. 2). 

‘ Anatomie des Frosches, Ecker-Wiedersheim, 2te Aufl., 1901. 
? Phil. Trans. Ser. B. Vol. 201, p. 91-132, 1910. 
3 Loe. cit. 
Sec. IV., 1912. 5. 
