Scieniific Intelligence — Zoology. 379 



astonishment in the country, that the fact was established by a regu- 

 lar investigation. This mule had been covered by a stallion horse; 

 but while she was with foal, the thing appeared so incredible that 

 she was considered as affected with dropsy, and her master wanted 

 to get quit of her. Eight months after the birth of the colt in ques- 

 tion, which, it may be mentioned, thrived well, an attempt was made 

 to cover her again, but without success. 



At the conclusion of his memoir, the author gives us the results 

 of a microscopic examination, which he undertook along with M. de 

 Martins, of the sexual organs of another mule. It was found that 

 the primitive ovule, the vesicle of the germ and the blastoderm, as 

 well as the oviduct and uterus, &c., are precisely the same as in the 

 mare and female ass, and that it is impossible to detect any anato- 

 mical condition to account for sterility. A beautiful engraving pre- 

 sents all the details of this investigation. 



I have made many attempts to produce hybrids among mammi- 

 fera, as I had formerly done among birds, but hitherto I have not 

 succeeded. The work in question confirms the conclusions I had 

 drawn from the examination of birds, namely, that, in the organs of 

 the sexual parts where the germs are developed, there are fewer dif- 

 ferences in female mules, compared with those of the female animals 

 from which they are derived, than in the male organs. Hebenstreet, 

 Bonnet, Gleichen, MM. Prevust and Dumas, have examined the 

 sexual organs of mules, and they have never met with the conditions 

 of a procreative sperm, that is to say, containing complete sperma- 

 tozoa. I know, moreover, that in the mules of birds, we find only 

 an incomplete production of what are called spermatic animals, and 

 Brugnone is the only writer who, contrary to the preceding experi- 

 ments, says that he found mobile fillets in the sperm of nmles. Some 

 years since, I begged M. Hausmann, of Hanover, since deceased, to 

 undertake new researches on this subject. This philosopher has em- 

 bodied his observations in an autograph memoir, which unfortunately 

 has not been published, but it appears that a mare which had been 

 several times covered by a nmle never became pregnant. The semi- 

 nal fluid of a male mule in season for the twelfth time, analysed after 

 covering a mare, contained no spermatozoa. 



Fronj all the facts hitherto collected, we may, therefore, conclude, 

 that wherever examples are alleged to have occurred of fertile copu- 

 lations of mules, they always refer to female animals ; that the pro- 

 creative faculty appears absolutely wanting in male hybrids ; and 

 that this fecundation, which is excessively rare, cannot take place 

 without the effective production of living and mobile spermatozoa. 



6. The Oil of Herrings. — M. de Quatrefages has addressed a note 

 to the Academy of Sciences on the extraction of the oil of herrings, 

 and the pieparation of tangrum, a manure which he considers fitted 

 to form a substitute for guano. 



The object of the note is to draw attention to some facts, too little 



