44 BRITISH COPE POD A. 



berland, where it haunts the shallow pools which are 

 scattered over a small extent of salt marsh near the 

 river side: these pools, being subject to the occasional 

 overflow of the tide, are, of course, brackish, and, 

 towards the end of summer, swarm with microscopic 

 and even larger life of various kinds. I have no doubt 

 that they would well repay a more minute examination 

 than I have been able to devote to them. It may be 

 interesting here to note the Entomostraca which I have 

 taken in this marsh : the Copepoda are Cyclops 

 cequoreus, Tachidius brevicornis, Temora velox, Delavalia 

 palustris, Ectinosom.a (sp.), Laophonte (sp)., Platy- 

 chelipus littoralis, Dactylopus tisboides, and possibly 

 others of which I have not kept note ; and besides 

 these, the following Osfcracoda occur plentifully : 

 Cythere castanea, Limnicythere inopinata, Cypris gibba, 

 Loxoconcha elliptica, Cytheridea torosa. 



As regards the particular species now under con- 

 sideration Delavalia palustris it remains to be noted 

 that it is scarce in comparison with the other Copepoda 

 in whose company it occurs, though a few specimens 

 may almost always be found in a gathering from the 

 Seaton Marsh. Though I have dissected several spe- 

 cimens very carefully I have not succeeded in finding 

 the lower foot-jaw ; I can scarcely doubt that it really 

 exists, as in other species of the genus, though perhaps 

 very small. The mouth-organs of these mud-loving 

 creatures are very liable to get obscured by adherent 

 dirt, and difficult to recognise even after long-con- 

 tinued maceration in solution of potash. 



