261 TRAXSACTIOXS, NATURAL HISTORY SOCIETY OF GLASGOW. 



XXXI. 



NOTES ON RHINCALANUS GIG AS, BRADY, 

 AND ECTIXOSOMA ATLANTICUM, BRADY 

 AND ROBERTSON. 



BY THOMAS SCOTT, F.L.S., NATURALIST TO THE FISHERY 

 BOARD FOR SCOTLAND. 



[Read 25th November, 1890.] 



Rhincalanus gigas was first observed by my son 

 (Andrew Scott) when looking over some tow -net 

 material collected at Orkney in 1889. He drew my 

 attention to two specimens, but I laid them aside 

 with the intention of examining them at my leisure, 

 and they were forgotten for a considerable time. 

 During the early part of the present year, I was 

 examining some tow-nettings collected about 22 

 miles south-east of Montrose in the beginning of 

 February, when another example was obtained. I 

 thereafter submitted specimens to Professor G. S. 

 Brady, F.R.S., who identified them as Rhincalaims 

 gigas, Brady. He stated at the same time that he 

 had some doubt as to Rh. gigas being really distinct 

 from Rh. cormitus, Dana. Rhincalanus has been 

 recorded from various places, but has not, so far as 

 I know, been previously observed in British waters. 

 It is fullj^ described in the Report on the Challenger 

 Copepoda. 



Ectinosoma atlanticum was fir.st described, under 

 the generic name of Microstella, from specimens 

 collected by Mr. E. C. Davidson in the open sea to 

 the West of Ireland (see Mon. Brit. Copep.). It is 

 an exceedingly small species. I have not yet had 

 time to measure the dimensions of any of the 

 specimens, but Dr. Brady gives ^ of an inch as 



