On the Sexual Products in Spongilla. 435 



oclivaccious, very slightly irrorated witli grey towards the base ; 

 the remainder of the wings pinkish grey, crossed with an in- 

 distinct irregular dark band, bordered externally towards the 

 apex with pale pinkish grey ; the spot at the end of the cell is 

 bright ochraceous. 



Expanse of wings 2f inches, 



Racjadia annulata. 



Upperside. Both wings stramineous, with the band, costal 

 margin of anterior wings^ and exterior margin of both wings 

 broadly ashy brown, crossed near the apex as far as the first 

 median nervule by an ashy-brown bar ; beyond that nervule 

 the bar is discontinued on the upperside, but it shows through 

 from the underside, where it is prolonged across both wings 

 to the inner margin. 



Underside. Anterior wings crossed by three ashy-brown 

 bands, the submarginal band having eight ocelli ; costal and 

 outer margins ashy brown. Posterior wings with three 

 bands, the middle band concave and the outer one with six 

 ocelli, the second, third, and fourth being the largest. All 

 the ocelli are black, with silver pupils, the iris ochraceous, 

 the second and third on the posterior wing enclosed ia one 

 iris. 



Expanse of wings 1| inch. 



LXIV. — On the Development of the Sexual Products in 

 Spongilla. By Karl Fiedler *. 



Since Lieberkiihn t in 1856 discovered both spermatozoa and 

 ova in Spongilla^ and thus for the first time demonstrated the 

 presence of these important structures in the sponges, the 

 history of their production has been treated of in a long 

 scries of spongological memoirs. The further develop- 

 ment of the freshwater sponge has also been of late years 

 repeatedly made the subject of investigation. The results 



* Translated from a separate copy from the ' Zoologischer Anzeiger,' 

 no. 266, 1887, communicated by the Author. 



t N. Lieberkiihn, "Beitrage ziir Entwicklungsgescliichte der Spon- 

 gilleu," in Miiller's Archiv fiir Anat. uad Physiol. 1856, p. 17, and also 

 " Zusatze zur Eiitwicklun^sgeschichte der SpongilleUj" ibid. p. 501. 



