686 Proceedings of the Royal Irish Academy. 



POLTCHJETA . 



No special records were kept of the numerous larval forms except 

 a few, wHch I happen to know hy name ; only two are recorded 

 here. 



Magelona. 



The free-swimming larval form was found on the following 

 dates : — 



1895. In May; abundant on the 24th. Specimens measiu'ed 



1 to 2 mm. in length. July 5th, one specimen, 3 mm. 

 in length. 



1896. March 16th. A few specimens about 2 mm. in length. 



August 28th and September 1st, a solitary specimen 

 on each date. 



1897. July 19th, 29th, and August 5th, a solitary specimen on 



each date. 



1898. March 30th and April 24th, a solitary specimen on each 



date. 

 Mitraria. 



This rare larval form was only seen in 1895. A sudden 

 swarm entered the harbour on April 10th, and disappeared on 

 April 22nd. A few specimens were also taken between May 

 13th and 27th. 



This larval form has been veiy rarely found in British 

 seas. It has been recorded from Plymouth (Boui-ne, 1889) 

 and Falmouth ( VaUentin, 1891). 



Watson (1898, 12th Ann. Rep., Liverpool Biol. Soc, p. 16) 

 has succeeded in connecting Mitraria with a Polychaete called 

 Oweiiia fiUformis. 



Autolytus, Sp. ? 



A few females, carrying eggs, were taken duiing the spring, 

 in the years 1895-98. It was twice seen in July, 1897, and 

 once early in JN'ovember, 1896 and 1897. The male, known 

 as Polylostrichus, was only seen twice, on April lOth, 1897, 

 and March 8th, 1898. 



Tomopteris onisciformis, Eschscholtz. 



This beautiful, transparent, free-swimming Polychcete is a 

 regular inhabitant of Valencia Harbour. During the early 



