LIXNEAN SOCIETY OF LOXUOX. 47 



witli tliis, this diabolic agency lias left as the end result a 

 segmented animal — the Vertebrate — in which with the greatest 

 cunning he has not only made the supra-int'iindibiilar brain the 

 exact counterpart of the supra-oesophageal and ths infra-infun- 

 dibular of the infra-oesoi)hageal, but lias grouped that nervous 

 system round a large epithelial bag, which has nothing to do with 

 a nervous system, but most ingeniously has been put in the exact 

 position of the cephalic stomach and oesophagus of the Arthropod 

 animal. To complete the story and give it an artistic finish, this 

 ingenious devil plants above the brain of the A^ertebrate impostor 

 two median eyes exactly in the position of the two median eyes 

 of the Palaeostracan. He does not put them therefor the purposes 

 of sight, for they are fuuctionless and degenerate in all Vertebrates, 

 but just for sheer mischief, and how he must have chuckled over 

 the happy thought of making them partly degenerate in the lowest 

 Vertebrates, for he well knew that in the Limulus and his con- 

 temporaries they were already markedl)'' degenerate and that they 

 were no longer the chief eyes but their place had been taken by 

 the large lateral eyes. 



Prof. MacBride has asserted again, witliout giving instances, 

 the statement so often made before, that 1 assume violent changes 

 of function. Again and again 1 have denied it, and shown that I 

 do not assume any such thing. Yet again 1 will go through tlie 

 list of resemblances and ask where this statement of MacBride's is 

 justified. The function and structure of the supra-infundibular 

 brain is the same as that of the supra-oesophageal ganglia ; the 

 two lateral eyes and the two median eyes are the same in the two 

 groups ; the median nose has the same structure, the same nerves, 

 and the same olfactory glomeruli in the two groups and even the 

 slight difference, that the nasal tube in Ammoccetes opens dorsally 

 and the olfactory passage in the Scorpion ventrally, vanishes after 

 von Kupffer's demonstration that this Ammoccetes nasal tube 

 originates as the tube of the hypophysis, which opens ventrally, 

 and the dorsal position is due simply to the growth of the upper 

 lip. Passing to the infra-oesophageal region, in both animals the 

 anterior part is devoted to the organs of mastication and the 

 posterior part to the organs of respiration ; there is no change of 

 function here, and 1 have given the evidence to show how the 

 actual masticating and respiratory organs of the one group have 

 insensibly shifted into those of the other group. Where are the 

 violent changes of function so far ? Then, if we pass into the 

 spinal cord region, are we to look for them in the muscles or in 

 the excretory oi'gans or in the coclomic cavities ? Why, the whole 

 evidence is that they are the same in the two groups ; no sign of 

 change violent or otherwise. 1 wonder what Prof. Macliride 

 means. Surely this scathing indictment is not bused on the 

 thyroid gland which, I must repeat yet again, is not a mucin 

 secreting gland but is a gland of great importance to the well 

 being ot the Vertebrate, apparently having something lo do with 



