8 ARKIV FÖR BOTANIK. BAND 17. N:0 12. 



Carica cannot be regarded as a well-known genus. Solms 

 in his monograph 1893 knew but 21 species, besides some 

 rather doubtful, imperfectly described ones. Since then, 

 very few new species have been described — in South Ame- 

 rica only two, viz. 



C. boliviana Rusby, Bull. New York Bot. Gard. IV, 1907 



and C. tripUsecta Herzog, Meded. Rijks-Herb. 27, 1915, both 



from Bolivia. 



In addition, there are two species described from the 

 West Indies, viz. 



C. jamaicensis Urb. S\'mb. Antill. VI, 1909 

 and C. fjortoricensis Urb. 1. c. IV, 1910. 



One species with very peculiar, five-horned fruits has 

 been discovered in California. 



C. caudata Brandegee, Zoe IV, 1894. 



C. tunariensis 0. Ktze, Rev. Ill (2) 101 is no Carica 

 but of doubtful systematic position and C. dolichaula D. 

 Smith, Bot. Gaz. XXIII, 1897 should rather be referred to 

 the genus Jacaratia. 



It is possible that still some more species may have 

 been described from the West Indies, Central America or 

 Mexico during the last few years but I do not think so.' 

 Consequently we may state now, when concluding this chap- 

 ter, that as yet 28 species of Carica are known to science, 

 but according to travellers' reports many new ones — from 

 the Andean countries especially — still remain to be de- 

 scribed. 



Cytology and embryology. 



The material for the cytological investigation was fixed 

 partly in Zenker's, partly in Flemming's and partly in 

 Carnoy's liquid. After washing it was preserved in 70 % 

 alcohol during the whole journey and imbedded in paraffine 

 after my return to Stockholm. The ZENKER-fixed material 

 proved to be excellent: hence that fixing-fluid may be re- 

 commended for Carica. 



In all species and individuals, here investigated, the 

 diploid chromosome number is 18 (Fig. 11). The 

 development and construction of the embryo-sac also agree 



