ANOMALOUS VEGETABLE STRUCTURES. 313 



it usually presents in the species an anomaly or monstrosity is produced. 

 These principles will, I believe, be found sufficient for the explanation 

 of all vegetable anomalies excepting those of colour, which are as yet 

 imperfectly understood, and they show that all, however apparently 

 differing, amount to variations of development of the organs belonging 

 to the specific type, there being a tendency characteristic of the species 

 to full or diminished, to equal or unequal development, and the ano- 

 maly being an alteration in the individual case from some cause acting 

 peculiarly upon it. Sometimes we perceive the cause, frequently it is 

 hidden from our view, and we only know it by its effect, but a little 

 experience guides us safely in its determination. In an earlier state of 

 the science abnormal forms either only excited a vague wonder, or were 

 even regarded with some dislike as interfering with the characters of 

 species or the rules laid down for their examination, whilst the fond- 

 ness of mere cultivators for some of them on account of their rarity or 

 beauty was considered as a proof of their ignorance. Yet no objects 

 can be contemplated more rich in instruction, more fruitful of sugges- 

 tions for improving our acquaintance with the real structure of plants 

 than these occasional deviations from their natural characters. We 

 inquire what the change really is which has taken place, and how it 

 may be brought vnthin the range of a law as real and as uniform as 

 those on which the ordinary appearance depends, but usually less 

 exposed to our observation and therefore the more interesting. Take 

 for example the case, of not very uncommon occurrence in cultivation, 

 of a Fuchsia, whose regular number of parts in the flower is four in 

 each circle, being found to have five parts in each. We readily ap- 

 prehend that an unusualsupply of nutriment has produced the phenome- 

 non, but how or why ? Is number in the circles of flowers variable 

 without rule, or would the abundance of nutriment cause the production 

 of additional parts having no relation to the symmetry of the flower ? 

 All our experience is against such suppositions. Let us, however, 

 recollect that five is the normal number of parts in each circle in Exoge- 

 nous plants, and that when in such plants the number four or a less 

 number habitually occurs, botanists attribute the reduction to a degree 

 of pressure causing abortion of one or more parts rudimentally existing. 

 We might then confidently anticipate that in a regular flower with 

 only one part deficient an increased supply of nutriment would some- 

 times restore the missing part as well as enlarge the others, and 

 the law of alternation being constant in such structures as this, we 

 should expect that one circle having five parts all the others would 

 VOL. m. V 



