1-42 TRANSACTIONS AND PROCEEDINGS OF THE [Sess. Lxm. 



concerning the nuclear union in the ascus, namely, that it 

 represents a true sexual act, we should be driven to the 

 same conclusion that each ascus represents a complete 

 individual. 



The occurrence of nuclear unions not involving a break 

 in the life-history might be regarded as militating against 

 the theory here put forward. And such nuclear unions 

 are stated to occur; but the conditions under which they 

 are stated to occur are such as to neither strengthen nor 

 weaken the case. Were an ascus or a basidium to lose its 

 power of producing spores, and to become sterilised in 

 order to take on new functions, it might, nevertheless, in 

 its youth exhibit nuclear fusions of a sexual or of a 

 deuterogamic nature. Xow, Mr. ]\Iassee (9), in addition to 

 recording a number of interesting facts in reference to the 

 origin of metuloids, cystidia, and other sterile cells of the 

 hymeniuni in Ascomycetes and Basidiomycetes, states that 

 in Lachnca alho-sp(idicca the large protective hairs borne on 

 the ascophore are formed by the union of the terminal 

 cells of two adjacent hy[)lui', and that Che two nuclei of the 

 cells coalesce. i\Ir. Massee, however, is unable to accept the 

 view that these protective hairs are sterilised asci ; he says, 

 " I think such" (protective hairs) "can not, by any amount 

 of ingenuity, be considered as aborted spore-producing 

 members." I confess 1 fail to see that there is any greater 

 difiiculty involved in the assumption that these hairs are 

 sterilised asci than there is in assuming that sterilisation 

 in iiowers has led to the production of staminodes, 

 perianth-segments, and pistillodes. I do not wish to 

 imply, however, that all sterile cells in hymenia are 

 sterilised asci or basidia ; on tlie contrary, there is strong 

 reason i'or believing that para{)hyses in some of the 

 Ascomycetes are merely vegetative hypha\ It is (piite 

 }>ossible that in one series of forms, in one representative a 

 vegetative hypha is modified to perform a certain function, 

 whilst, in another representative, a ])asidium or an ascus 

 is metamoriihosed to perform precisely the same function. 

 In addition to these nuclear fusions in the Ascomycetes, 

 there are others stated to occur in Angiosperms that 

 involve no bic^ak in the life-history. Strasburger records 

 and figUT'CiS unions taking place l)ctvveen nuclei in the 



