STEUCTUBE AND DEVELOPMENT OE EEISSNEr’s FIBRE. 29 
relations. To rentier intelligible this somewhat involved 
matter, I have reproduced in Text-fig. 1 two of Sargent’s 
figures, one (a) being taken from his preliminary paper. 
Text-fig. 1. 
An exact )'eprodnction of two of Sargent’s figures to show the 
difference between liis eaidier (’00) and later (’01) accounts of 
Rcissner's filjre and its relations to structures in the niid-lu'ain. 
The first (a) is taken from his earlier paper (’00) and shows the 
course of Reissner's fil)re correctly, but the posterior com- 
missure is identified (erroneously) as the torus longitudi- 
nal is {tor. hj.). In B. taken from his latest work ('04-). the 
posterior commissure (ro'msji.) and torus longitudinalis 
{tor. hj.) are correctly identified, b\it a second branch of 
Reissner's fibre has been added, to which the description 
originally given of the j)iece ventral to the posterior commissure 
is now made to apply. 
