238 REVIEWS. 



of the importance to be attached to the analogy ; but we may ask 

 whether the resemblance between the smaller water lilies and Brasenia 

 to Hydrocharis and Limnobium in one direction, and to Menyanthes 

 and Limnanthemum in another, is not quite as striking, though it sug- 

 gests no idea of near relationship. Certainly when the flower and 

 fruit are not procurable, we might well be in doubt of which of these 

 genera we had obtained the foliage. We cannot but strongly censure 

 the practice of some botanists, amongst whom is Mr. Clarke, of speak- 

 ing of cryptogamous and phanerogamous as two great divisions of the 

 vegetable kingdom, thus disguising the fact that the latter includes 

 two divisions, as well separated from each other, and by as important 

 characters, as either is from cryptogamous ; just as in zoology, we 

 know of nothing more misleading than the use of the division into 

 vertebrata and invertebrata, when each great branch of the latter is as 

 distinct from the others as any of them is from vertebrata. Curiously 

 enough it is among Cryptogamous — flowerless or spore-bearing plants, 

 whose growth commences from a primordial cell, without an embryo 

 being formed and preserved iu a seed — that we have made the farthest 

 advances towards a true and good classification, the full recognition of 

 which would have been no disadvantage to Mr. Clarke in making his 

 comparisons. The sub-kingdom naturally falls asunder into three 

 good classes, each of which has the same number of alliances, under 

 which all the orders or families are readliy arranged. "We have first 

 Thallogens, or Thallophytes, with no proper distinction of stem and 

 leaves ; with no chlorophyll, no stomata, and the lowest reproductive 

 type, though always, we believe, two cells intermingle their contents 

 to form a spore capable of germination. Here are ranged Fungales, 

 Lichenales, and Algales. Secondly, Anogens, with stomata and the 

 green colour of vegetation depending on the presence of chlorophyll, 

 but with no vascular system, and reproduction in a prothallus which 

 is temporary, the plant producing successive ones periodically. Here 

 rae found Charales, Hepaticales, and Muscales. Thirdly, Acrogens, 

 with an imperfect vascular system, and reproduction from a prothallus 

 in which the fertilized archegonium developes the spore-producing 

 plant, of which the prothallus usually resembles an initial condition. 

 Here are placed Equisetales, Lycopodales and Filicales. We doubt 

 much whether this exposition of the Acotyledonous or Sporigenous 

 sub-kingdom, on the correctness of which we rely with great confi- 

 dence, and which affords the best indications we have of what we may 



