1914] MARTIN— LEGUMINOSAE 165 



7. Saxton, W. T., On the development of the ovule and embryo sac in Cassia 

 tomentosa. Trans. S. Afr. Phil. Soc. 18:1-5. pis. 1, 2. 1907. 



8. Schleiden, M. J., and Vogel, T., tJber das Albumen inbesondere der 



Leguminosen. Kaiserl. Leopold.-Carol. Deutsch. Akad. 19: pts. 1 and 2. 

 1838 and 1842. 



9. Shoemaker, D. N., Notes on the development of Hamamelis virginiana. 

 Johns Hopkins Univ. Circ. 21:86, 87. 1902. 



io. Strasburger, E., Einige Bemerkungen iiber vielkernige Zellen und Embry- 

 ogenie von Lupinus. Bot. Zeit. 38:845-854, 857-868. figs. 64. 1880. 



11. , Die Angiospermen und die Gymnospermen. Jena. 1870. 



12. , Zur Santalum und Daphne. Ber. Deutsch. Bot. Gesells. 3:105- 



113. pi. q. 1885. 



13. Tulasne, M., Nouvelles etudes d'embryologie vegetal. Ann. Sci. Nat. 

 Bot. IV. 4:96, 97. 1855. 



14. Webb, J. E., A morphological study of the flower and embryo of Spiraea. 

 Bot. Gaz. 33:451-460. figs. 28. 1902; and Bot. Gaz. 34:246. 1902. 



EXPLANATION OF PLATES VIII-XI 



Trifolium pratense 



Fig. 1. — Young ovary showing the two ovules and placenta; X330. 

 Fig. 2. — Young nucellus showing one sporogenous and one parietal cell; 

 X1560. 



Fig. 3. — Young nucellus with a row of 4 archesporial cells; both integu- 

 ments are prominent; X1500. 



Fig. 4. — Young nucellus with 4 archesporial cells; inner integument is 



just beginning to show; X1560. 



Fig. 5. — Cross-section of nucellus with 3 megaspores, 2 of which are in 

 synapsis; X1500. 



Fig. 6. — Young nucellus with one mother cell in synapsis; the integuments 

 are well advanced; X1200. 



Fig. 7. — Nucellus with a row of 4 megaspores; two large dense cells lie 

 in line below the megaspores; parietal cell has not divided; X1200. 



Fig. 8. — Four megaspores with lower one functioning; X1500. 



Fig. 9. — A binucleate embryo sac eating its way into the chalazal end of 

 the nucellus; X1560. 



Fig. 10. — A 4-nucleate embryo sac; the divisions at each end have been 

 in the direction of the long axis of the sac; integuments well advanced and 

 outer is thickened at micropylar end; the ends of the nucellus and the inner 

 integument are filled with starch; X880. 



Fig. 11. — An 8-nucleate sac, with linear arrangement at antipodal end; 



micropylar end of nucellus being destroyed; embryo sac quite vacuolate; 

 X920. 



Fig. 12. — Polars in contact near the egg apparatus; nucellus more 1 r- 

 sistent; X1200. 



