248 Mr. J. W. Howell on the Structure of the Capsule 



Some of these questions comprise several others. To solve 

 them two things only are necessary, accuracy and perseve- 

 rance. M. Vaucher has afforded us an example of both these 

 qualities. His history of the Conferva is remarkable for its 

 precision in the explanation of new and delicate facts. His 

 last work required the average duration of man's life, and we 

 may say, in general, that during sixty years M. Vaucher rarely 

 turned aside from botany. From it he derived lively gratifi- 

 cation ; the result of his works has enriched the science ; let 

 us hope that others may endeavour to imitate him, and let us 

 ever religiously preserve the memory of a philosopher so well 

 entitled to our respectful recollection. Alph. DeC. 



XXXVI. — On some hitherto unnoticed peculiarities in the 

 Structure of the Capsule of Papaveraceae ; and on the Nature 

 of the Stigma of Cruciferas. By J. W. Howell, Esq., 

 M.R.C.S. 



The capsule of Papaver apparently bears so close a resem- 

 blance to that of Nymphaea, that it forms one of DeCandohVs 

 reasons for considering the Papaveraceae and Nymph&acece to 

 be allied*. The capsule in each genus is syncarpous, with 

 ovuliferous dissepiments, and is crowned with a many-rayed 

 stigma, the number of rays corresponding to that of the dis- 

 sepiments. The chief structural difference hitherto observed 

 between these capsules consists in that of Nymphcea being 

 composed of several carpels surrounding the axis, and having 

 the dissepiments formed by the juxtaposition of the ovulife- 

 rous sides of the perfect cells with intermediate plates of con- 

 necting cellular tissue ; whilst in Papaver the inflected sides 

 of the conjoined carpels not being continued to the axis, the 

 imperfect ovuliferous dissepiments project only midway into 

 the cavity of the capsule, and thus leave it one-celled. 



On a more attentive examination, however, a difference will 



* " Ob structuram fructus et stigmatis Papaveri valcle similem." — Regni 

 Veget. Syst. Nat. vol. ii. p. 42. 



This similarity of structure is repeatedly alluded to by this author; thus, 

 in " Nymphceacea — Styli * * * connati stigmatibus supra urceolum peltatim 

 (exacte ut in Papaver e) radiatis basi connatis apice liberis," vol. ii. p. 39. 

 Again : " * * * structura fructus Papaveris parum recedit a vera Nupharis 

 structura," p. 43. Again : " Papaveracece accedunt hinc mediante Papa- 

 vere ad Nymph&aceas," p. 68. 



In ' Flore Franc,,' DeCandclle included Nymphcea and its immediately 

 allied genera in Papaveracece, in which this great botanist followed the 

 example of Linnaeus, who had previously referred Nymphcea to his twenty- 

 seventh Order, Rhceadece, which very nearly corresponds with the Papa- 

 veracece of modern authors. 



