350 E. T. NEWTON. 



section 13 (fig. 8) the peduncles have reached and joined the 

 outer calix on each side, the caulicuhis having" almost disap- 

 peared. In section 14 the peduncles have joined tce inner 

 calices also, and this connection is seen in each sectioiitcS 

 far as the 19th, the calices at the same time exhibiting their 

 deepest curvature. In section 20 (fig. 9) the peduncle on 

 each side has entirely disappeared, the trabecida alone being 

 seen in the middle line below. In the succeeding sections 

 the traheculce become gradually less, but can be traced as 

 far as the 28th section. Passing back from the 18th or 19th 

 section, the calices get less curved and smaller, and traces of 

 them are last seen in the 25th section. The commissures 

 to the infra-oesophageal ganglia are reached in the 18th 

 section, and become larger and larger through the remainder 

 of the series. 



The Traheculce loith their Cauliculi and Peduficles. — The 

 trahecula in each hemisphere commences abruptly in the 

 5th section, and is seen extending from the middle line 

 below (where it abuts upon, but apparently does not join, its 

 fellow of the opposite side) obliquely upwards and out- 

 wards to join the lower part of the ccndiculus (fig. 6). 

 Passing backAvards the trahecula continues about the same 

 size until it has received the peduncle, behind which point it 

 gradually decreases (fig. 9), and is altogether lost before the 

 back of the brain is reached (see figs. 15 and IT). 



Each cauliculus is a large mass of nervous matter, contin- 

 uous with the outer part of the trahecida, the junction 

 extending as far back as the hinder part of the peduncle 

 (fig. 15). Seen from the front it curves upwards and out- 

 wards, presenting a convex surface inwards, and a concavity 

 outwards (figs. 5, 6, and 17). Its thickness from before 

 backwards is greater than it is from side to side, and conse- 

 quently it presents an oval figure in horizontal sections. 

 The upper portion is truncated by being closely applied to 

 the under surface of the outer calix, while the inner convex 

 surface is closely overlaid by the inner calix. The line of 

 demarcation between the calices and the cauliculus is very 

 distinct, and there seems to be no nervous connection 

 between them. Above and in front this ccndiculus extends to 

 the front surface of the hemisphere, where it appears to be 

 merely covered by the thin investing membrane of the brain. 



The peduncle, or stem of the corpora fungiformia, arises 

 from the trahecula by a wide base extending from the 6th 

 to the 20th section. Its upper part is very much smaller 

 than the cauliculus. In a front view the peduncle is seen to 

 continue upwards the curve of the trahecula, and to present 



