RISAUMUR 275 



books. Their history as related in Kirby and Spence 

 is taken almost wholly from E^aumur. 



Animals which Increase hy Budding^ 



Biological discoveries of the highest interest not 

 relating to insects (in the modern sense), nor to 

 Reaumur's own work, occupy the concluding pages of 

 his last preface. Trembley had lately made known the 

 existence of an animal (Hydra), which increased by 

 budding, and when cut in two, gave rise to two 

 new animals. Trembley's discovery, communicated to 

 Reaumur in 1740, was shortly afterwards set forth by 

 Trembley himself in his classical Memoires pour servir 

 d, I'histoire d'un genre de Polypes d'eau douce (1744). 

 The name Polype, since so extensively employed, was 

 suggested by E^aumur. 



In this same preface E^aumur was able to give a 

 preliminary notice of Bonnet's discovery of the multi- 

 plication of a fresh-water worm by artificial division. 

 Bonnet's fuller account appeared three years later (1745) 

 in his Traite d'lnsectologie.^ 



The discoveries of Trembley and Bonnet were followed 

 by a number of experiments on the multiplication of 

 animals of low grade by artificial fission. E^aumur 

 found that planarians (" sangsues limaces "), Stylaria, and 

 earthworms could be increased in this way. Gruettard 

 and Bernard de Jussieu experimented on starfishes, and 

 made it clear that they could at least reproduce lost 

 rays. Trembley investigated a fresh-water polyzoan 

 which he called the polype d pannache (Lophopus), 

 and showed that it produced new individuals by 

 budding. 



At this time a question was reopened which had been 



1 Vol. VI, preface. ^ Infra, p. 284. 



