RECOMMENDATIONS. 481 



Desideratum noticed in Mr. Taylors Report on Mineral 



Veins. . 



A correct account of the affinity that the contents of a vein 

 bear to certain of the rocks in which the fissure may be situated. 



ZOOLOGY. 



The Committee recommend to the consideration of Zoologists 

 the following subjects of inquiry : 



*1. The use of horns in the class Mammalia; the reason of 

 their presence in the females of some, and their absence in those 

 of other species ; the connexion between their development and 

 sexual periods ; the reason of their being deciduous in some 

 tribes, and persistent in others. 



*2. The use of the lachrymal sinus in certain families of the 

 Ruminantia. 



*3. The conditions which regulate the geographical distri- 

 bution of Mammalia. 



*4. The changes of colour of hair, feathers, and other ex- 

 ternal parts of animals ; how these changes are effected in parts 

 usually considered by anatomists as extra-vascular. 



*5. The nature and use of the secretions of certain glands 

 immediately under the skin, above the eyes, and over the nos- 

 trils, in certain species of the Grallatores and Natatores ; the 

 nature and use of the secretion of the uropygial gland. 



*6. How long and in what manner can the impregnated ova 

 of fishes be preserved, for transportation, without preventing 

 vivification when the spawn is returned to water. 



*7. Further observations on the supposed metamorphosis of 

 Decapod Crustacea, with reference to the views of Thompson 

 and Rathke. 



*8. Further observations on the situation of the sexual or- 

 gans in male spiders, and on their supposed connexion with the 

 palpi. 



*9. The use of the antennfe in insects. Are they organs of 

 hearing, of smell, or of a pecuHar sensation ? 



*10. The function of the femoral pores in Lizards, and the 

 degree of importance due to them as offering characters for 

 classification. 



BOTANY. 



1. That Botanists in all parts of Great Britain and Ireland 

 be invited to compose and communicate to the Meeting of the 

 1833. 2 1 



