80 The Ottawa Naturalist [October 



SEA SQUIRTS. 



By Professor E. E. Prince, Commissioner of Fisheries, Ottawa. 



No one who has spent a few hours on the sea shore, turning 

 over weed-covered stones, can have failed to notice clusters of 

 leathery objects, styled by the fishermen sea peaches, sea apples, 

 sea potatoes, etc. They are of various shapes, as these names 

 indicate, and differ in colour, some bright pink, others scarlet, 

 or orange, or pure white, or stone colour, and other tints. Some 

 strongly resemble leathery grapes, or coarse plums, or even 

 small leather bottles, while many are semi-transparent, and 

 not unlike green-glass flasks, one or two inches long. They 

 cling by the base to stones and other objects, and frequently 

 hang from the underside of shelving rocks, others are upright 

 and stalked, resembling a brown potato on a long stem (like 

 Boltenia), others are jelly-like colonies (such as Amarousumi) , 

 and some occur as long strings of clear glassy creatures, floating 

 as Salpa does, near the surface of the sea. On touching them 

 they squirt out two thin jets of water, from an aperture at the 

 top, and another at the side. They have the appearance of 

 motionless vegetables, and are scientifically called Tunicates, 

 or less accurately, Ascidians, but by more philosophical natur- 

 alists they have been dignified with the name Urochordates. 

 They merit some notice in these pages for two reasons, viz: 

 their very special scientific interest, and for a second important 

 reason, that they have formed the subject of some most re- 

 markable original investigations by Dr. A. G. Huntsman, of 

 the University of Toronto, a distinguished worker among our 

 younger Canadian biologists. The high scientific interest pos- 

 sessed by the Tunicates, or Sea Squirts, arises from the fact 

 that they have been looked upon as the ancestral progenitors 

 of the human race (or rather of all vertebrates), and about 

 them Andrew Lang wittily wrote: 



"The ancestor remote of Man, 

 Says Darwin was the Ascidian." 



The additions to our knowledge of Canadian Ascidians, 

 due to Dr. Huntsman's labours, are a source of just pride to 

 our scientists. Dr. Huntsman was trained under Professor 

 Ramsay Wright, whose retirement from his Toronto chair 

 zoologists on this continent will never cease to deplore. Laborious 

 and successful work at the three Dominion Government bio- 

 logical stations, during many years, led to Dr. Huntsman's 

 appointment by the Biological Board recently to the responsible 

 position of curator in charge of the marine and fishery investi- 



