51(3 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



work which has ever been published in relation to the struct- 

 ure and development of algae. It includes 51 folio steel en- 

 gravings from drawings by Riocreux and Bornet. The text 

 is principally by Bornet, as Thuret died before the work was 

 finished. The illustrations and account of the development 

 of the Pliwosporew and Fucacece are very complete. The 

 Development of Botrydium granulatum, by Woronin and 

 Rostafinski, shows that species pass through several different 

 phases, which had been considered by preceding botanists as 

 distinct species. There are several different modes in which 

 the zoospores are produced, and some are furnished with 

 one and others with two cilia. The latter unite in twos or 

 some larger number, and may be said to conjugate, forming 

 what Rostafinski calls an isospore. The second paper, on 

 the Development of Acetabularia mediterranean is by Pro- 

 fessors De Bary and Strasburger. The growth of the plant 

 until the formation of the spores had previously been 

 studied by Woronin at Antibes. In the present paper the 

 spores are shown to contain zoospores, and so should rather 

 be called zoosporangia. There is also described a peculiar 

 basal process. Dr. Goebel, who studied for a time at the 

 zoological station at Naples, gives the result of his observa- 

 tions on Ectocarpus pusillus and Giraiidia sphacelarioides. 

 He found that the zoospores conjugated very much in the 

 same manner as in some of the green Zoospores. Conjuga- 

 tion has also been observed by Reinke in Monostroma 

 bullosum and Tetraspora lubrica. The effect of the action 

 of light on the motions of zoospores has been studied inde- 

 pendently by Stahl and Strasburger. In the Record for 

 1877, we referred to an article by Sachs, in which he de- 

 scribed the figures formed by small particles floating in 

 liquids, and suggested that the figures assumed by zoospores 

 were of a similar nature, and due to currents. Stahl and 

 Strasburo-cr, however, a^ree in thinking that there is a di- 

 rect influence of light on the motions of zoospores, and that 

 they are not caused wholly, at least, by currents. Stras- 

 burger divides zoospores into two classes: aphotometric, 

 those not influenced by variations in the intensity of the 

 light ; and photometric, which are so influenced. 



Dr. Wittrock, in the Proceedings of the Royal Swedish 

 Academy, furnishes an account of the spores in the Mesocar- 



