ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 741 



North American Pteridophyta.* — W. R. Maxon publishes notes on 

 a form of Woodwardia spinulosa, Adiantinn modestum, and a new 

 sub-species of Polystichum munitum from Guadelupe Island, Mexico. 

 A. A. Eaton f gives an account of Equisetum Icevigatum and its varieties. 



A. V. Osmun % describes some characteristics of Equisetum scirpoides 

 and its habitats, and regards it as less rare than has been supposed. 

 W. N. Clute § gives a list of 222 ferns collected in Jamaica. J. 

 Reverchon || records 51 ferns and 15 fern-allies as occurring in Texas. 



B. F. Bushel has compiled a list of 59 ferns from the same State with 

 habitats. A. A. Eaton ** publishes a critical and historical note on 

 Isoetes riparia var. canadensis and /. Dodtjei, which he finds to be identi- 

 cal, and which he unites under A. Braun's Ms. name /. canadensis. 

 H. L. Lyon |f gives a list of 60 pteridophytes of Minnesota, five of 

 which are new records for the State. 



Bryophyta. 



Development of Spermatozoids in Marchantia.Jt — Ikeno has in- 

 vestigated the development of the antherozoids in Mar chant ia poly- 

 morphs with especial relation to the occurrence of centrosomes and 

 their relation to cilia formation. Centrosomes were observed clearly in 

 the inner cells of the antheridium. The centrosome appears first as a 

 body inside the nucleus ; it wanders out of the nucleus and divides into 

 two bodies which take up opposite positions on the rounded nucleus. 

 The nucleus becomes elongated in relation to the centrosomes, and 

 between the latter spindle-fibres begin to appear, which on the dis- 

 appearance of the nuclear wall make their way into the nuclear cavity 

 and form a complete spindle. The centrosomes disappear at the end 

 of the division ; whether they are dissolved in the cytoplasm or taken 

 up by the nucleus is doubtful. After the division which separates the 

 sperm-mother-cells the centrosomes, however, do not disappear but take 

 on the function of blepharoplasts, that is, the centrosome moves to the 

 periphery of the cell, becomes elongated, and develops the two cilia. 

 The author finally discusses the question of the nature of the centro- 

 some and blepharoplast. 



European Mosses.§§ — W. Limpricht continues the supplement to Die 

 Lavbmoose of his late father, K. G. Limpricht, advancing the work 

 from Bryum to Hypnum, gathering up the various additions that have 

 been published since the main text was printed. A. Mansion and J. Ch. 

 Sladden|||| publish descriptive and critical notes on Rhacomitrium sude- 

 ticinn and Grimmia airata, additions to the Belgian flora. A. Hansen %% 



* Fern Bulletin, xi. (1903) pp. 38-40. t Tom. cit., pp. 40-44. 



I Tom. cit., pp. 44-6. § Tom. cit., pp. 54-9. 



|| Tom. cit., pp. 33-8. 



If Bull. Torrey Bot Club, xxx. (1903) pp. 343-58. 

 ** Tom. cit., pp. 359-62. 



ft Minnesota B t. Studies, ser. iii. (1903) pp. 245-55. 

 XX Beih. Bet. Oentralbl., xv. (1903) pp. 65-88 (3 pis., 1 fig. in text). 

 §§ Rabenhorst's Kryptogamen-Flora, iv. 3, Lief. 39 (1903) pp. 769-S32. 

 i| || Bull. Soc. 11. Bot. Belg., xli. 2 (1903) pp. 48-55. 

 «[f Bot. Tidsskr., xxv. (1903) pp. 243-51. 



