29 i 



SCIENCE 



[N. S. Vol. XLI. No. 1051 



So far as I have been able to observe, notb- 

 ing unusual occurs in the early stages of 

 development of the prothallia of any of tbe 

 three species. The prothallia of Aspidium 

 isussimense and of Lastrea chrysoloba grow 

 to a large size and are tsrpically heart-shaped. 

 The prothallia of Pellwa adiantoidis are 

 much smaller and in some respects resem- 

 ble those of Pellwa atropurpurea, in which 

 species I described apogamy in 1910.^^ Anther- 

 idia are produced in large numbers on many 

 of the prothallia of each of the three species 

 here under consideration. The antherozoids 

 are actively motile and appear to be normal in 

 every respect. Archegonia have been ob- 

 served on some of the prothallia of Lastrea 

 chrysoloba. 



On the well-developed cushion of the pro- 

 thallium of Aspidium isussimense, usually at 

 some distance back of the apical notch, a 

 number of papillate projections appear. These 

 projections frequently occur in groups. Some- 

 times each consists of a single cell, but more 

 frequently of a single row of cells. In this 

 portion of the prothallium, usually after the 

 projections have been formed, a compact mass 

 of cells appears which develops into an embryo. 

 At an early stage in the formation of this 

 apogamous embryo, tracheids are produced. 

 The developing embryo never produces a foot. 

 The primary leaf as a rule is formed in ad- 

 vance of the primary root. The stem appears 

 later than the leaf and the root. Even while 

 the embryo is very young, numerous scales 

 appear on the petiole of its primary leaf. 

 These resemble the scales so characteristic of 

 the mature sporophyte. 



The prothallia of Pellcea adiantoidis also 

 produce embryos apogamously. The devel- 

 opment of the embryos appears to be 

 similar to that described in my previous paper 

 for that of Pellwa atropurpurea. In a number 

 of cases in my cultures the embryo has already 

 formed the primary leaf and the primary root. 



When the embryo of Lastrea chrysolola is 

 about to form, a small light region appears 

 between the apical notch and the cushion. In 

 this region the embryo is developed. In all 



1 Bot. Gaz., 42, 400-401, 1910. 



of my cultures the apogamously produced em- 

 bryo has just begun to project above the sur- 

 face of the prothallium. Embryos developed 

 from a fertilized egg have not been found. 

 When prothallia-bearing archegonia are placed 

 in a drop of water on a slide and examined 

 microscopically, the archegonia can be ob- 

 served to open, but antherozoids do not appear 

 to be attracted to them. 



While the prothallia of these species of 

 ferns were being grown, numerous cultures of 

 other species maintained under the same con- 

 ditions of nutrition, light, temperature and 

 moisture, contained prothallia bearing anther- 

 idia and archegonia, and in some cases em- 

 bryos were produced upon these prothallia as 

 a result of fertilization. W. N. Steil 



Univbrsitt of "Wisconsin 



THE AMEBICAN SOCIETY FOB PHASMA- 



COLOGY AND EXPERIMENTAL 



TEEBAPEUTICS 



The sixth annual meeting of the Pharmacolog- 

 ical Society was held in St. Louis at Washington 

 University Medical School on December 27-30, 

 1914. There were five scientific sessions, three of 

 them being joint meetings with the other mem- 

 bers of the Federation of American Societies for 

 Experimental Biology, the Physiological Society, 

 the Biochemical Society and the Society for Ex- 

 perimental Pathology. 



The following officers were elected in the 

 Pharmacological Society for the year 1915: 



President: Torald Sollmann. 



Secretary: John Auer. 



Treasurer: Wm. deB. MaoNider. 



Additional memhers of the council: Worth Hale 

 and D. E. Jackson. 



Memhership Committee: S. J. Meltzer (term 

 expires 1917). 



Election of New Members: The following candi- 

 dates were approved by the membership com- 

 mittee, passed by the council and elected by the 

 society: Dr. F. C. Becht, University of Chicago; 

 Dr. W. H. Brown, Rockefeller Institute; Dr. F. 

 L. Gates, Rockefeller Institute. 



The attendance was excellent, but the eastern 

 section of the country was not as well represented 

 as could be desired. 



The scientific sessions were opened on Monday, 

 December 28, at 9 a.m. by a joint meeting of the 



