204 The Ohio Naturalist. [Vol. VIII, No. 1, 



Fig. 11. Typical microspore of same date. 



Longitudinal section of an anther, showing the frothy gela- 

 tinous substance about the pollen grains. The anther walls 

 consist of the epidermis, endothecium, two intermediate lay- 

 ers, and the tapetum. Jantiary 29, 1906. 



Section of a two-celled pollen grain. Apiil ,30, 190G. 



Longitudinal section of an ovule, showing the archesporial cell 

 which is the megasporocyte. August 18, 1906. 



Longitudinal section of an ovule, showing the three small, non- 

 functional megaspores and the large functional one. August 

 26, 1906. 



A longitudinal section of a megasporangium, showing two- 

 celled embryo-sac with the disorganizing nuclei of the three 

 vestigial megaspores. September 2, 1906. 



The ovule cut longitudinally, showing the four-celled embryo- 

 sac with a few of the many disorgianzing nucellar cells shown. 

 September 8, 1906. 



Longitudinal section of an eight-celled embryo-sac, showing the 

 long dense cone, a trace of the egg nucleus Ij'ing just below 

 the synergids, the large definitive nucleus below the egg, the 

 three small antipodals and a few of the disorganizing cells of 

 the nucellus. kay 21, 1906. 

 Fig. 19. A tip of an eight-celled embryo-sac, showing the contorted 

 ridges on the cone. The egg lies in the median line just below 

 the synergids with the definitive nucleus at its side. May 

 21, 1906. 



Another figure, to show the double point of the cone of the 

 embryo-sac, the definitive nucleus lies at the side of the egg 

 in this one also. May 21, 1906. 



A voung embrvo with suspensor below the cap of endosperm 

 tissue. July 9, 1906. 



Outline sketch of a young embryo, shoAving the cotyledons, 

 root tip and fragment of suspensor. July 21, 1906. 



Outline sketch of an older embryo with cotyledons, stem tip, 

 root tip and root cap. July 28, 1906. 



Addition to List of Dragonflies of Canada.* 



Under date of June 3, 1907, Mr. E. P. VanDuzee kindly calls 

 my attention to an omission in the paper cited. In the 

 list of papers relating to Canadian dragonflies I omitted Mr. 

 Van Duzee's paper, List of Dragonflies Taken Near Buffalo, 

 N. Y., Journ., N. Y., Ent. Soc, Vol. V, June, 1897, pp. 87-91, 

 in which he records the capture of Anonialagrion hastatum Say at 

 Point Abino, Ontario. I failed to list this witi'. 1be other Cana- 

 dian species-. 



Bluffton, Ind. E. B. Williamson. 



The writer would be pleased to receive reports of any obser- 

 vations on the southward migration of the Monarch Butterfly 

 {Anosia plexipptts) during the early part of October. 



Herbert Osborn. 



♦Published in Ohio Natur.m.ist, Vol. VII, No. 7, May, 1907, pp. 148-150. 



