Scientific Intelligence. 177 



III. By Successive and Co-existent Separable Forms. 



a. External Gemmation. b. Internal Gemmation. 



A. Forms little different. All the forms produce eggs. 



Hydra. } Gyrodactylus. 



B. Forms markedly different. Last forms only produce eggs. 



*^* Last Forms produced. 

 Generally : 

 Medusa. } Fluke. 



Locally : 

 Salpa. } Aphis. 



These various modes of Representation of the Individual 

 are ultimate facts. One is neither more nor less wonderful 

 or explicable than another ; any theory which pretends to 

 account for the Successive and co-existent forms of the Aphis- 

 individual must also account for the successive forms of the 

 Beetle- individual or of the Horse-individual — since they are 

 phenomena of essentially the same nature. 



When the forms of the Individual are independent it be- 

 comes desirable to have some special name by which we may 

 denote them, so as to avoid the incessant ambiguity of the 

 two senses of the word individual. For these forms the 

 Lecturer some time ago proposed the name " Zooid." Thus 

 the Salpa-individual is represented by two Zooids ; the Fluke 

 by three ; the Aphis by nine or eleven, &c. 



The use of this term is of course a mere matter of con- 

 venience and has nothing to do with the question of Indivi- 

 duality itself. 



SCIENTIFIC INTELLIGENCE. 



1. A Letter to Sir John W. Lubboch, Bart., F.R.S., " On the 

 Stability of the Earth's Axis of Rotation." By Henry Hennessy, 

 Esq., M.R.I. A., 8fc. (Communicated by Sir John Lubbock. — The 

 author refers to a communication to the Geological Society by Sir 

 John Lubbock, in which he appeals, in support of the possibility of 

 a change in the earth's axis, to the influence of two disturbing causes, 

 which appear to have almost entirely escaped the notice of Laplace and 

 Poisson, in their investigations on the stability of the earth's axis of 



VOL. LIU. NO. CV. — JULY 1852. M 



