TRANSACTIONS OF SECTION D. 763 



as the author has shown elsewhere, the medullary and cortical tissues have an 

 elaborate system of protoplasmic connections between the contents of the cells, 

 ■which ofive the rows of cells more or less the characters of sieve-tubes. Now in 

 the higher plants indift'usible proteids are conducted from the place oF manufacture 

 to the ])lace of consumption or storajie aLm^' the sieve-tubes in the phloem. 

 Hence there can scarcely be a doubt that what may be called the sieved tissue of 

 the Fuccicece is to be correlated with the large quantity of proteids they contain, 

 and the necessity that arises for their distribution to different jjarts of the thallus. 



6. On Assimilation and the Ei>oliifioi). of Oxygen by Green Plant Cells. 

 By Professor Pkingsheim. 



7. Some Words on the Life-history of Lycopods. By Dr. M. Treub. 



8. On a point in the Morpholoriy o/ Viola Tricolor. 

 By Professor Baylet Balfour. 



9. On the Morphology of some Ccesalpinea and the Value of Morphological 

 Criteria. By Professor Haetog. 



TUESDAY, SEPTEMBER 6. 



The following Reports and Papers were read : — 



1. Discussion on the Present Aspect of the Cell Question, 



Professor Schiifer opened the discussion, which was continued by Professors 

 Lankester, Krause, H. M. Ward, Carnoy, and Ilartog, and jMessrs. Gardner and 

 Sedgwick. 



2. On Polar Bodies. By Professor Weismann, and hy Professors Lan- 

 kester and Keause, Messrs. Gardner, Sedgwick, H. M. Ward, 

 Carnot, and M. Haetog. 



3. Itep>ort of the Committee on the Herds of Wild Cattle in Chartley ParJc 



and other Paries in Great Britain. — See Reports, p. 135. 



4. Further Experiments upon the Protective Value of Colour and Markings 



in Insects. By E. B. Poulton. 



The experiments undertaken in 1886, of which a short account was given in a 

 paper read before Section D at Birmingham, led to such interesting results that I 

 determined to renew the investigation during the present year.^ At the same time 

 the range of the inquiry has been widened, and for the first time a mammal has 

 been included in the list of insect-eating vertebrates used in the experiments. For 

 this purpose a marmoset has been employed, and this animal appears to be highly 

 insectivorous. With the kind help of Mr. A. G. Butler I have been able to add 

 largely to the number of experiments made with birds, and these results have been 

 especially needed. In addition to the species of lizards and frogs made use of last 



' For the complete account of the experiments in 1886, see a paper by the author 

 in Proc. Zool. Soc, London, March 1, 1887, pp. 191-274. 



