CH. XVII. ZOOLOGY. 143 



From 1663 to 1666 the two friends travelled together 

 over England, France, Germany, and Italy, making col- 

 lections of animals and plants, and Willughby took a pleasure 

 in using his wealth to add to the knowledge of his poorer 

 companion. Soon after their return Ray was made a fellow 

 of the Royal Society, and Willughby was not long before he 

 received the same honour. Willughby now married, and 

 though Ray continued his travels alone, yet a great part of 

 his time was spent at Middleton Hall, where the two friends 

 made experiments upon sap in the trees and the way it 

 flows. 



In this way they worked together till, in 1672, Mr. 

 Willughby died of a fever, leaving a sum of sixty pounds a 

 year to Ray, and begging him to bring up his two little sons 

 and to continue his works on Zoology, which he had left un- 

 finished. The way in which Ray fulfilled these requests fully 

 showed the affection which he felt for his lost friend. He 

 brought up the boys till they were removed from his care by 

 relations ; and as to the works, he edited them with so much 

 care and such a touching desire to give every credit to 

 Willughby, that much of the work which must have been 

 Ray's stands in his friend's name, and in fame, as in life, it 

 is impossible to separate them. 



I can only give you a very general idea of the kind of 

 classifications which Ray and Willughby adopted, for a mere 

 list of classes would be neither interesting nor useful to you. 

 The first book, which was on Quadrupeds^ was published by 

 Ray in 1693. He divided these first, as Aristotle had done, 

 into oviparous, or those that are bom from eggs, like frogs 

 and lizards ; and viviparous, or those which are born alive, 

 Jike lambs and kittens. He then divided the viviparous 

 quadrupeds into those which have the hoof all in one piece, 



