General Notes. [June, 



umberland iron ore of Rhode Island. By M. E. 

 :ay 1 8, 1881. 8vo, pp. 4. Extracts from the Pro- 



GENERAL NOTES. 



The Quillworts of North America.— Probably few of the 

 readers of the Naturalist have given much time to the study of 

 the grass-like or rush-like plants commonly designated as the 

 quillworts, and included in the genus Isoetes. They are Pterido- 

 phytes, that is, they belong to the great group of plants lying 

 next below the Phanerogams, and distinguishable from the still 

 lower plants by the possession of fibro-vascular bundles in their 

 stems and leaves. The equisetums, ferns, adder tongues, and 

 ground-pines are among their relatives, and of these, the last 

 named have by far the closest relationship. Although the plant- 

 body of quillworts is much simpler than that of ground-pines and 

 ferns, their reproductive organs are of a higher order, and for this 

 reason they are to be regarded as among the highest of the 

 Ptendophytes. In fact, in some respects, as for example in the 

 germination of the microspores, there is an evident relationship 

 10 the Gymnosperms. The one, two or three small cells observ- 

 able in the pollen grains of conifers are but little different from 

 and are clearly homologous with the rudimentary prothallium of 

 the quillworts. 



The natural interest these plants possess, on account of their 

 position so near the boundary line separating Ptendophytes from 

 the lower Phanerogams, will be greatly enhanced by the 'excellent 

 work recently done by Dr. Engelmann, the results of which have 

 just been published in the Transactions of the St. Louis Academy 

 of Sciences under the caption of "The Genus Isoetes in North 

 America," and also separately issued as a pamphlet of thirty-four 

 pages. With his usual thoroughness the author has left little 

 more to be desired in this admirable monograph. The history of 

 the species, both as to discovery and publication is given with 

 great fullness. From this we learn that " the first notice which we 

 have of an Isoetes in North America is given in Pursh's Flora" 

 (A. D. 1806). During the succeeding quarter of a century but 

 few specimens were collected. From 1831 when Robbins gath- 

 ered Isoetes riparia near Uxbridge. Mass., to the present time 

 there has been a steadily increasing attention ^iven to the species 

 by collectors. 



The morphological and biological characters are well worked out 

 'Edited by Prof. C. E. Bessey, Ames, Iowa. 



