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structure of cruciferous flowers. Considerable difference of opinion 

 (or, rather, explanation) has prevailed respecting the floral structure 

 in the order of Cruciferse. Moquin-Tandon and Webb, after giving 

 their explanations in detail, sum up their views thus : " The floral 

 type of Cruciferae is quaternary. The calyx is composed of 4 leaflets, 

 the corolla of 4 petals, the receptacle has 4 staminiferous glands, the 

 andrceceum 4 stamens, the gynceceom 4 pistils, the fruit 4 carpidia. 

 These verticils alternate regularly. Two stamens in the habitual state 

 of the flower have been transformed into two pair by multiplication 

 [dedoublement), and two pistils have disappeared by abortion : hence 

 the andrceceum has two component parts more than it should have ; 

 the gynoeceum two less. The four staminiferous glands are more or 

 less irregular or incomplete, and are found above, below, or by the 

 side of the filaments. Their volume has caused a change in the 

 position of two stamens and of two calycinal leaves, which makes the 

 androeceum and the calyx appear biverticillate." This view differs 

 materially from that given in Lindley's 'Vegetable Kingdom.' Such 

 differences, however, are truly only differences of words, or, at least, 

 of artificial technicalities : they are not realities in nature ; although 

 most systematic botanists evidently believe that they are making pro- 

 found researches into nature, while they are simply showing how far 

 the natural facts accord with or differ from their own technical inven- 

 tions and conventional rules; such inventions and rules being, by a 

 fiction of the imagination, regarded as discovered laws of nature. 



The letters of Dr. Thomson are well deserving the attention of 

 those botanists who interest themselves with the geographical relations 

 of plants. The observations of a good and zealous botanist, travelling 

 from India to the lofty lands of central Asia, must possess no little 

 claim to attention ; and all the more where they correct false informa- 

 tion previously put forth by other parties. We have always felt con- 

 vinced that Dr. Royle's writings, bearing on the geographical botany 

 of Asia, were wanting in that degree of exactness which is necessary 

 for scientific reliance, and yet contradiction or correction seemed out 

 of reach. The following incidental statement in one of Dr. Thomson's 

 letters throws some light on the matter, by showing that Dr. Royle's 

 factshave been erroneously reported: " Royle publishes many plants from 

 Kunawur ; but the localities are incorrectly given in his book, owing, 

 apparently, to the native collectors having always stated the name of 

 the nearest town or halting place, instead of the mountain where the 

 specimens were gathered. Thus Lippa, Soongnum, Rogee, and Pan- 



