24 DK. M. T. MASTEKS 0>' THE MOHPHOLOGY or THE MALYALIlS. 



to analogy, as has been done by Asa Grray, Beutham, and others, 

 but also to organogeny, as studied by Payei', Duchartre, Baillon and 

 A. Dickson. Unfortunately the latter writers are not in accord- 

 ance one with another on all points. Duchartre* considers that 

 the petals and stamens of Mallows are identical in their origin, 

 being developed from five papillae, alternate wdth the sepals ; and 

 that each papilla in process of time divides so as to give origin 

 to a petal and a cluster of stamens, the union of the five clusters 

 forming the column. This view receives the supi)ort of Asa Gray tj 

 who cites in its favour the case of Sidalcea^ before mentioned. 



Payer J dissents from the conclusions of Duchartre, and asserts 

 that the petals originate earlier than, and distinct from, the sta- 

 mens, and moreover that the latter organs are developed centrifu- 

 gaily, i. e, from the centre to the circumference, and not from the 

 circumference to the centre, as stated by Duchartre. The appear- 

 ances in the young bud of Glossosfemon conform with the views 

 of Paver, as the staminode is in advance of the stamens in its 

 development, and of the stamens that are attached to it the 

 uppermost are evidently developed first ; so that, assuming the 

 staminode, with the stamens, to be the analogue of a digitate 

 leaf, the central lobe or staminode is developed first, the lateral 

 lobes or fertile stamens subsequently, and in regular order, 

 from above downwards, as appears to be the general rule in 

 the case of compound stamens. All observers seem to be agreed 

 that the fertile stamens originate in front of the petals, and 

 not alternately with them ; so that there is really or appa- 



y,/ rently an exception to the law of alternation. There are seve- 

 ral ways by means of which this anomaly may be explained ; 

 but as they are for the most part of a hypothetical nature, I shall 

 merely indicate them briefly. ' 



In the first place, then, the opposition of the stamens to the 

 petals may be accounted for on the supposition that an outer" 



^ row of stamens is suppressed ; but, in the majority of instances^ 

 the existence of this outer row is purely hypothetical, while m 

 those cases (such as Glossostemon) where a second row is con- 

 sidered by some to exist, the law of alternation is still interfered 

 with, as the inner row (the staminodes) is placed opposite to 

 the sepals, and not opposite to the petals, as it ought to be. 

 In the next place, it is possible to arrive at an explanation of the 



* Ann. Sc. Ifat. 3rd ser. vol. iv. p. 123. t Cl^en. Flor. Am. vol. ii. p- ^*'' 



{ *Traite d'Organogenie Coniparee de la Fleur' (1857), p. 29, tab. 6, 7, 8- 

 See also Baillon, ' Adansonia,* vol. ii. p. 1G6. 



