M. A. Giard on the Genus Entoniscus. 141 



place of abode. If in a plant we make an incision and 

 introduce into it a living branch of another plant, there is 

 produced a graft by inosculation and union (raccordement) 

 of the vessels ; exactly the same thing takes place in our 

 animals. 



" I do not know whether, hitherto, any animals which 

 graft themselves have been known. It seems to me that the 

 opposite of what I have just indicated had rather been 

 observed ; it had been seen that the eggs of one animal depo- 

 sited in the body of another animal produce tumours, which, 

 by bursting, form regular wounds. This is the case with 

 those flies which lay their eggs under the skin of cattle, in 

 their nostrils, or their intestines, and which thus occasion a 

 tumour, and afterwards a sort of blister, the matter from 

 which nourishes their progeny *. Certainly the two para- 

 sites of the crabs just mentioned are rather grafted animals 

 than animal galls. These latter are met with only in plants 

 attacked by animals. The egg of an insect deposited upon a 

 plant becomes soaked with the juices of the latter and grows 

 at its expense ; but it is not strictly correct to say that the 

 canals of the egg anastomose with those of the plant and 

 become continuous with these latter " f. 



It is evident, from Cavolini's description and the figures 

 which accompany it, that in this case, as in that of Sacculina, 

 the supposed ovigerous sac is nothing but a crustacean de- 

 graded by parasitism ; and the form of the young enables us 

 to recognize immediately that we have to do here with an 

 Isopod belonging to the group Bopyridas. The few errors of 

 detail which exist in the description of the larva or of the 

 adult animal will be referred to hereafter. They cannot, 

 however, in any way modify this first conclusion. As will 

 be seen, these observations of Cavolini were very remarkable 

 if we consider the period at which they were published. 



Unfortunately, in this question of the Bopyridae, as in that 

 of the Suctoria, the bibliography is complicated in a regret- 

 table manner ; the very great difficulty of bringing together 

 the original memoirs, often written in languages and published 

 in repertories which are but little known, causes one to con- 

 tent one's self with quoting them from imperfect abstracts or 

 unfaithful translations. Hence one has several times taken 



* u CEstri larvae latent intra pecorum corpus, ubi per totam hyemem 

 nutriuntur : fonticuli vice gerunt &c.'' — Linnee. 



See also the works of Vallisnieri and of Reaumur. 



t See Cavolini, ' Memoria sulla generazione dei pesci e deigranchi' 

 (Napoli, 1787), pp. 190-194, pL h. figs. 17, IS. We have thought it 

 worth while to translate this curious passage in extenso, because now-a- 

 days Cavolini's memoir is hardly to be procured. 



