THE CLASSIFICATION OF THE TILOPTERIDACE^. 183 



be, at most, a variety of Sc. speciosa^ and this view has 

 received considerable support by the fresh information 

 gained. The same also applies probably to Scapliospora (?) 

 Kingii, Farlow> 



With regard to Haplospora Vidovichii (Kiitz.) Bornet,'^ 

 or Heterospora Vidovichii (Bornet) Kuck., it seems unde- 

 sirable to leave it in the Tilopteridacese, because the in- 

 teresting discoveries recently made by Kuckuck tend to 

 show that it differs in several essential respects from the 

 Tilopteridacese. To sum up the differences, Heterospora is 

 not polysiphonous below, as are always Haplospora and 

 Tilopteris ; it has, so far as is known, no pluri-locular tubu- 

 lar 'antheridia; the monospores are uni-nucleate, whereas 

 in Tilopteris and Haplospora the spores contain more than 

 one nucleus ; and it has uni-locular zoosporangia, which are 

 entirely unknown in Tilopteris and Haplospora. All these 

 features, which are characteristic of Heterospora Vidovichii, 

 tend to separate this plant from the Tilopteridacese, and 

 several of them bring it nearer to the Ectocarpacese, among 

 which it might be provisionally placed in a sub-order Hetero- 

 sporese, or a new order for its reception might be created, 

 as it differs from all the true Ectocarpacese in having mono- 

 spores. 



Further, with regard to Choristocarpus tenellus (Kiitz.) 

 Zan., Kuckuck^ is of opinion that it should not be included 

 in the Tilopteridacese as suggested by Zanardini. The facts 

 that this plant has apical growth and that the apparent 

 monospores are gemnise, in conjunction with the data given 

 above, fully justify this attitude. 



^ W. G. Farlow, On New England Algae {Bulletin of the Torrey 

 Botanical Club, May, 1882). 



2 Bornet, Notes sur quelques Ectocarpus, 1891 {Bullet, de la Soc. hot. 

 de France, No. 6). ^ i.e., p. 313. 



