520 JOUENAL OF THE KOYAL HORTICULTURAL SOCIETY. 



In farm practice, however, in the majority of cases, sufficient farmyard 

 manure cannot be spared to give such heavy dressings, and it is therefore 

 important to note that in these experiments, as in those previously 

 reviewed in this Journal, a dressing of 10 tons of dung with a complete 

 mixture of artificials gave a very profitable return. The best mixture 

 consisted of 4 cwts. superphosphate, 1 cwt. sulphate of potash, and 

 2 cwts. sulphate of ammonia. It was noted that there was less disease 

 among the potatos where potash was added to the mixture of artificials. 



" Mr. Walker points out that in generalising on the effects of the 

 various manures on the potato crop, he has taken the average of all the 

 centres, but he recommends those who are interested in the subject to 

 study carefully returns from centres situated in their own district, as it is 

 well known that the nature of the various soils and climatic conditions 

 have much to do with the effect of artificial manures. He adds, more- 

 over, that the results have been aftected in no small degree by the use of 

 different varieties of potatos at the several centres, inasmuch as some 

 varieties, e.g. ' Up-to-date,' respond in a greater degree than others, e.g. 

 * Main Crop,' to heavy manuring, and future experiments should, in his 

 view, be conducted with special reference to this point." — li. N. 



Pkimulas. 



PrimulaceaB, Anatomy of. By E. Decrock (Aim. Sc. Nat., Botan. 

 i. xiii. p. 1 ; 90 figures; lUOl). — This paper of 200 pages gives a sum- 

 mary of five years' work, the full account of which is in preparation as a 

 monograph. The method has been applied to many natural orders, to 

 examine the internal structure of as many species as possible, to compare 

 the results, and to deduce the general features or differences of the group. 

 Montpellier, where the work was done, is well situated for a study of 

 Primulacece, so that not only dead but .many living plants have been 

 examined. The paper is divided into four parts : —(1) review of litera- 

 ture ; (2) the general anatomy of the order ; (3) the general histology of 

 the order ; (4) descriptive anatomy of the genera and species examined. 

 From its general anatomy the order falls into two groups, Primula the 

 type genus of one, Lysimachia of the other ; the distinguishing characters 

 of the two groups are given in a summary (p. 56). The part on general 

 histology is a review of the epidermal, the fundamental, and the con- 

 ductive systems. The descriptive anatomy gives details of species 

 examined. A convenient summary gives in a few pages some interesting 

 results. The Primiilacec? are essentially moisture-loving (hygrophilous) 

 plants like Primula, but there are a few xerophytes suited to dry con- 

 ditions ; the genus Androsace includes a series from hygrophilous to 

 xerophytic. M. Decrock does not agree with the alleged existence of 

 polystely in the stem of some species. — TF. G. S. 



Resin Structures. 



Resin and the Resin-producing' Structupes in the Polypodi- 

 aeese and a few Phanerog'ams, The formation of. By Dr. F. 



Hohlke (Berlin) (Beih. Bof. Cent. bd. 11, ht. 1, pp. 8-45 ; 3 plates).— A 

 very important description and discussion of everything connected with 



