10 Transactions of the Royal Microscopical Society. 



rounded by a structureless membrane, which extends, in the form 

 of the above-mentioned sheath, over the nerves. The interspaces of 

 the ganghonic bodies, and the bundles of nerve fibres within the 

 ganghon, are filled up by a semi-fluid substance containing in- 

 numerable granules. 



\_Erritta. — In my paper on the development of the blooil corpuscles, in 

 No. LXIL, February, 1874, p. 49, line 10 from top, for "blood," read "brood"; 

 and IS lines from top, for " blood," read " brood." Also the words " nat. size " on 

 Plate LI. is, of course, an error.] 



