346 Dr. Pringsheim on the Germination of Algae. 



Thamnophilus hyperythrus, Gould. 



Crown and sides of the head, all the upper surface and tail, slaty- 

 black ; wings brownish-black, with a spot of white at the tip of each 

 of the coverts, forming three semicircular rows across the wing ; 

 chin, breast and abdomen rich dark chestnut-red, gradually blend- 

 ing on the flanks and vent into the dark hue of the upper surface ; 

 bill black ; feet olive-brown. 



Total length, 7 inches ; bill, 1 ; wing, 3^ ; tail, 2| ; tarsi, 1 . 



Hab. Chamicurros in Peru. 



Remark. — I believe the above to be the description of a female. 



XXXIV. — On the Impregnation and Germination of the AlgcB. 

 By Ur. Prixgsheim. 



To the Editors of the Annals of Natural History. 



Gentlemen, April 25, 1855. 



The author having forwarded me a copy of the resume of his 

 researches lately laid before the Berlin Academy, with a request 

 that I will make them known in England, I have drawn up a 

 brief abstract of them, and beg to oflFer this for insertion in your 

 pages. 



I am, Gentlemen, yours very truly, 



Arthur Henfrey. 

 Vaucheria. 



Besides the large ciliated zoospore, so fully described by linger 

 and others, the Vaucheria possess organs, known by the names 

 of capsules or sporanges and horns. These were regarded by 

 Vaucher as sexual organs, and he believed that the horns per- 

 formed the functions of anthers, stating that they emitted a 

 dust-like product, which he compared to the pollen of Phane- 

 rogamia, and imagined to exert a fertilizing influence upon the 

 contents of the sporanges. This view has been contested by 

 subsequent authors, some of whom have stated that a conjuga- 

 tion takes place, between the horn and the sporange, analogous 

 to that seen in Zygnema, &c. Karsten (Botan. Zeitung, 1852, 

 p. 89) has given an elaborate description of such a process. 

 Dr. Pringsheim believes that Vaucher approached nearest to the 

 truth, and states that the supposed conjugation is altogether 

 imaginary. According to his recent researches, the horn is 

 really an antheridium, since its contents become converted into 

 spermatozoids, bodies which when in motion appeared stick- 

 shaped, but when allowed to come gradually to rest, presented 

 the a])pearancc of minute clear vesicles, 1-180 of a line in dia- 



