270 Proceedings of the Royal Physical Society. 



to the selected type, I would discuss separately each genus, 

 showing how one species differed from another, and how 

 they were related to their own particular genus, just as 

 we might compare the leaves belonging to a particular twig, 

 and indicate how they were individually attached. The 

 genera and species having been considered, I would conclude 

 with a definition of the family, never using vague terms, such 

 as " usually " or " generally," and always mentioning the ex- 

 ceptions in detail. 



Having treated all the families of the suborder in this way, 

 I would next compare the various families with each other, 

 indicating how they essentially differed from each other, 

 and how they had departed from what were supposed to be 

 the ancestral forms. All the other suborders would be 

 treated in the same way, with this difference, that whenever 

 it was possible, instead of giving an exhaustive statement of 

 the characters of the type selected, I would simply show how 

 it differed from the original type which served to illustrate 

 the first suborder. When all the suborders had been con- 

 sidered in this way, I would next compare the various sub- 

 orders, indicating, when possible, along what routes they had 

 severally travelled from their starting point — what amount 

 of elaboration they had undergone — how much they had 

 been specialised or degraded — whether they were at or near 

 their climax, or approaching their decline — what amount of 

 parallelism there was amongst them, and in what respects 

 they chiefly differed — also, how their present compared with 

 their past distribution — and how far they or their ancestors 

 had been traced into previous epochs. 



XX. Note on " Deserted Spawning Grounds of the Herringr 

 By J. CossAR EwART, Esq., M.D. 



(Read 19th March 1884.) 



Certain inshore banks around the British coast, and along 

 the shores of Norway and Sweden have long been frequented 

 by the herring when about to spawn. Some of these banks 

 have been visited, chiefly in the autumn, while others have 



