136 Fortpflanzung. 



Toutes les Mucorinees , heterogames ä quelque degre que ce soit, offrent, 

 dans l'histoire nucleaire de leurs zygospores, les memes phenomenes essentiels: 

 fusion de noyaux, degenerescence nucleaire. Chez les unes, le premier pheno- 

 mene est dominant: il a Heu quand la zygospore est encore jeune. Les zygospores 

 de ce type rappellent Celles des Mucorinees isogames, connues au point de vue 

 histologique. Chez d'autres, le phenomene preponderant est la degenerescence; 

 la fusion n'intervient que tres rarement entre les noyaux en nombre restreint. 



C. L. Gatin (Paris). 



365) CoUins, G. N. and Kempton, J. H., An Improved Method of Artificial Pol- 

 lination in Corn. In: U. S. Dept. Agr. Bur. Plant Ind., Circ. 89, S. 1—7, 1912. 



Describes a new method for the transfereuce of pollen in controlled fertilization of 

 maize without risk of contamination from foreign pollen. A description of the method 

 is as follows: 



"The method here proposed involves the use of strong paper tubes about 4 inches 

 in diameter and 40 inches long. Longer tubes are sometimes necessary for very tall 

 plants, and for short plants a piece may need to be torn off. To apply the tubes, one 

 end is pushed over the tassel and wired firmly at a point just below the upper end of 

 the last leaf sheath. The other end of the tube is then brought down and passed over 

 the young ear and securely wired. In pulling the tube down to the ear the tassel will 

 be beut to one side in such a way that as soon as the anthers open the pollen falls 

 down the tube and comes in contact with the silks. To protect against any foreign 

 pollen which may be present on the tassel or ear when bagged, the tubes should be 

 put in place four or tive days before the silks are expected to appear. The greatest 

 difficulty in applying the tubes is to allow for the elongation of the stalk above the 

 ear. Unless guarded against, this elongation will break the stalk at the base of the 

 tassel and then push through the paper, making an opening where foreign pollen can 

 enter. To prevent this breaking of the tube, two extra €olds are taken where the paper 

 is cemented, making a strip an inch or so wide composed of four thicknesses of paper. 

 In adjusting the tubes this strip is placed on the upper side, causing the tube to form 

 an even curve instead of bendicg sharply at one point." 



Since the tubes remain in place untii all dauger from foreign pollen is past, Pro- 

 vision must be made for the increasiug size of the ear. This can be done by using a 

 coiled instead of a straight wire to fasten the tube to the ear. The coiled wires are 

 easily made by wrapping the wire around any small cone-shaped object, like the point 

 of a lead pencil. The advantage of the cone-shaped coil over a cylindrical coil is that 

 the tension necessary to straighten the coil is nicely graduated when a cone-shaped coil 

 is used. Pearl (Orono). 



366) Couibes, R., Sur une methode de culture des plantes superieures en 

 milieux steriles. In: C. R. Acad. des Sc. Paris, Bd 154, Heft 14, S. 891—893, 1^12. 



Cette methode est voisine de celles qui ont 6te imagines anterieurement par divers 

 auteurs. C. L. Gatin (Paris). 



367) Hart, E. B., McColluin, E. V., Steenbock, H. and Humphrey, G. C, (Madison, 

 Wis., University of Wisconsin), Physiological Effect on Growth and Repro- 

 duction of Rations Balanced from Restricted Sources. In: Wisconsin Agr. 

 Exp. Stat. Research Bulletin, 17, S. 131—205, 1911. 



A report of the results of an extended and thorough study of the effects of restric- 

 ted diets on dairy cows and their progeny. The experiments cover four years. „There 

 is evidence from the data that there is a distinct and important physiological value to 

 a ration not measurable by present chemical methods or dependent upon mere supply 

 of available energy. While the lattcr are important and give valuable data for a start- 

 ing, point, they are nevertheless, inadequate as final criteria of the nutritive value of a 

 feed. Animals fed rations from ditferent plant sources and comparably balanced in re- 

 gard to the supply of digestible organic nutrieuts and production therms were not alike 

 in respect to general vigor, size and strength of olfspnng and capacity for milk secre- 

 tion. Animals receiving their nutrients from the wheat plant were unable to perfornr 

 nonnally and with vigor all the above physiological processes. Those receiving their 

 nutrients from the corn (= maize) plant were strong and vigorous, in splendid condition 

 all the time, and reproduced young of great weight and vigoi-. Animals receiving their 

 nutrients from the oat plant were able to perform all the physiological processes of 



