72 , . Dr. G. C. Wallich on the Process of 



the chance of the birth of a male. I operated in accordance 

 with the directions of Prof. Thury, and the success again con- 

 firmed the truth of the process which had been communicated 

 to me — a process the application of which is direct and very easy. 



Besides my Durham bull, I obtained six other bulls, of a 

 cross-breed between the Durham and Schwitz, which I intended 

 for work : by selecting cows of the same colour and size, I ob- 

 tained very well-matched pairs of bulls. 



My herd consists of forty cows of all ages. 



To sum up, I have made in all twenty-nine experiments ac- 

 cording to the new process, and all have given the desired pro- 

 duct, male or female : 1 have had no case of non-success. All 

 the experiments were made by myself, without the intervention 

 of any other person. 



I can consequently declare that I regard the method of 

 Prof. Thury as real and perfectly certain, hoping that he will 

 soon be able to profit all breeders and agriculturists in general 

 by a discovery which will regenerate the business of cattle- 

 breeding. 



(Signed) G. Cobnaz. 



Montet, Feb. 10, 1863. 



XI. — On the Process of Mineral Deposit in the Rhizopods and 

 Sponges, as affording a Distinctive Character, By G. C. 

 Wallich, M.D., F.L.S., &c. 



In a paper published in the Number of the * Annals ' for Decem- 

 ber last. Professor Max Schultze adduces evidence in support of 

 the opinion that the siliceous spicules found within the chambers 

 of certain Foraminiferous shells do not constitute integral por- 

 tions of these organisms, but are the products of entozootic 

 sponge-growth, — the evidence in question being based on the 

 strictly Foraminiferous type of the shells in which such spicules 

 occur, on the presence of the latter being only occasional, on 

 their position and distribution when met with, and on the cha- 

 racters of sponge-sarcode as compared with " the organic sub- 

 stance remaining after specimens [of Polytrema'] preserved in 

 spirits^' have been decalcified by subjection to dilute hydro- 

 chloric acid. 



But whilst this may be regarded as the circumstantial evidence 

 in the case, the opinion advocated by Professor Schultze appears 

 to me to be sustained by proofs of a more direct and generally 

 applicable nature. These I shall now proceed to notice. 



According to Dr. Bowerbank*, "in the early stage of their 



* " On the Anatomy and Physiology of the Spongiada;," ' Philosophical 

 Transactions of the Royal Society ' for 1858, p. 281 et seq. 



