. Maryland geological survey. Carruthers and allied forms, and which thereis no reason for including in the family Cycadacese. It has been shownby Wieland* that fruition was the culminant event in the life of most,if not all, the trunks which he investigated, fruits not being produced ? Seward, Jurassic Flora, 1904, pt. ii, p. 44. Capellini and Solms-Laubach, 1891, Mem. R. Accad. Sci. Inst. Bologna (5),vol. ii, p. 161. Seward, loc , American Fossil Cycads, 1906. Maryland Geological Survey 315 until vegetative maturity. It would follow, if the method just men-tioned were pursued, th
. Maryland geological survey. Carruthers and allied forms, and which thereis no reason for including in the family Cycadacese. It has been shownby Wieland* that fruition was the culminant event in the life of most,if not all, the trunks which he investigated, fruits not being produced ? Seward, Jurassic Flora, 1904, pt. ii, p. 44. Capellini and Solms-Laubach, 1891, Mem. R. Accad. Sci. Inst. Bologna (5),vol. ii, p. 161. Seward, loc , American Fossil Cycads, 1906. Maryland Geological Survey 315 until vegetative maturity. It would follow, if the method just men-tioned were pursued, that a BennetUtes which was not mature enoughto show indications of flowering would be a Cycadeoidea, or an accidentof preservation might equally determine the question, an altogether un-desirable state of affairs/ It is very doubtful if specific determinations based upon externalform and surface features have any real value aside from their practicalutility, and it seems quite probable, as various writers have pointed out,. Fig. 6.—Sketcli map of the world showing the approximate distribution ofthe existing cycads. and as is fully admitted by Prof. Ward, that his determinations basedon megascopic characters cannot be looked upon as having real specificvalue, but simply as the most expedient method of handling the immenseamount of material which passed through his hands, the specific namesaffording convenient pegs on which to hang the morphological andstructural details which will result from a study of their histologicalfeatures. Nine species have been recognized by Prof. Ward in the ^ See Wieland, Amer. Journ. Sci., vol. xxv, 1908, p. 97. 316 Systematic Paleontology Maryland area, and these are here retained unaltered, although it isvery probable, as already stated, that this is too large a number. In view of the constantly increasing evidence of the abundance andextent of variation in the cycad-like plants during the Mesozoic, it hasseemed proper to adopt the siiggestion of
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