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Part III. — Seventh Annual Report 



projection of the mouth. Most of the Pleurobrachiae ranged from \ to | 

 an inch. The free ova of this species had the embyros well advanced, 

 while many of the smallest had only recently escaped. 



The surface-net beyond the Bay showed for the most part the same 

 forms, with the addition of a few larval Peachice on Thaumantias. 



From the beginning to the end of the month Plutei of diverse kinds 

 and at various stages thronged the bottom-net; moreover, many post-larval 

 Echini, Spatangoids, sand-stars, and brittle-stars were also captured in the 

 same net. Similar features occurred in the open water beyond the Bay. 

 They were seldom obtained in the mid-water net, except a few post-larval 

 forms in the latter region. In the surface-net, on the other hand, they 

 were more abundant than in either of the foregoing. Besides various 

 Plutei at all stages, there were the Auricularia-stage, Mitraria-larvse, post- 

 larval Echini and brittle-stars. Some of the long-spined larvae were § and 

 § in. across. The abundance of young Echinoderms in the surface 

 and bottom-nets was a marked feature. They form in their older stages a 

 favourite food of many fishes, but whether the long spines prove protective 

 to the larvae in their pelagic condition is yet an open question. 



The larval annelids still held a conspicuous place in the pelagic fauna 

 of August, and the forms which were recognised in the bottom-net were 

 for the most part the same, viz., larvae of Nerine, Spio, and Polydora. 

 Young Terebellids often occurred in the transparent tubes, which are 

 narrow at one end, dilated at the other, like the tube of Pectinaria. 

 Larval and post-larval forms of Polynoe\ some of them reaching \ of an 

 inch in length, were also frequent. The younger long-bristled larva; of 

 Polydora were especially common. Young Capitdlae were likewise 

 frequently met with. Tomopteris appeared comparatively seldom. The 

 use of the bottom-net off the Bell Rock and south-east of the Island of 

 May showed that the same types abounded in this region. 



The mid-water net captured Tomopteris more frequently than the 

 bottom-net, along with an occasional Nereis — probably from touching the 

 bottom or from pelagic sea- weeds or debris. The larval forms of Nerine, 

 Polytwe and the Terebellid in the tube were also obtained. The mid- 

 water net was less productive of annelids this month than the bottom 

 and the surface-nets. 



In the surface-net larvae of Nereis appeared at the beginning of the 

 month and on the 20th. The various iYmVie-larvae were also frequent 

 throughout the period, along with the forms above mentioned. The very 

 young (not larval) stages of Magelona papillieornis, Fritz Muller, was 

 captured in this net towards the end of the month. Tomopteris was 

 procured only once. The chief feature of note in the nets near the Bell 

 Rock was the occurrence of a very young example of Polynoe pellucida. 



The profusion of the larval and young annelids in the bottom- and 

 surface-nets is a feature of interest in connection with the food of post- 

 larval fishes. The larval annelids, indeed, attained their maximum this 

 year in August in these nets. 



In the bottom-net there was no diminution of the Copepoda and other 

 minute crustaceans as contrasted with July ; indeed they seemed even 

 more plentiful. Acartia longiremis was abundant throughout the entire 

 month, often in myriads, and Halitemora longicornis was nearly as 

 frequent. Ceniropages typicus was often obtained, and the same may be 

 said of Longipedia coronata. Pseudocalanus elongatus was perhaps a little 

 less frequently met with than Oithona spinifrons, the latter on one occa- 

 sion being numerous, and the females bearing ova about the middle of the 

 month. Calanus finmarchieus did not appear in this net in the Bay in 

 August, but in the open ground near the Bell Rock, as well as 15 miles 



