82 The Ottawa Naturalist [October 



in the northern waters of Alaska, and as Dr. Huntsman observes, 

 "perhaps overlap" in Behring Sea. Some species seem to be 

 very local, while others are world-wide in their range. The 

 familiar Pelonaia corrngata occurs in both oceans, and in the 

 Arctic as well, and presents in all localities the same features; 

 "they do not seem to differ in any respect," as Dr. Huntsman 

 notes. Alas, they are the homeliest in looks of all the Tuni- 

 cates! The same ubiquity applies to the greenish transparent 

 Ciona intestinalis. Phallusia ceratodes appears, on the contrary, 

 to be very local, and is a species first found and named by Dr. 

 Huntsman, and "quite distinct from any yet described." In 

 contrast are forms like AsciJiopsis paratropa, a new species 

 described by the author, and very distinct, yet closely related 

 to species from Corean seas, from Northern Europe, and from 

 Ptiget Sound, which latter is, however, less than a hundred 

 miles south of Departure Bay, where it was first discovered. 



But if the colours, the forms, and the distribution of these 

 strange animals present such striking features, their life-history, 

 physiology and anatomy are, to the popular mind, even more 

 extraordinary. Thus, they possess a heart, without valves, 

 and ventral in position, below the base of the endostyle. The 

 heart, in all true invertebrates possessed of that pulsating 

 organ, is dorsal in position, but in man and the Vertebrata it is 

 on the ventral or under side, as in Tunicates. It is enclosed 

 in a pericardium, and pulsates with a progressive vermiform 

 movement, and every few minutes it reverses its action, and 

 drives the blood in the opposite direction. Thus the heart's 

 contractions drive the blood now this way, now that way, a 

 curious characteristic feature of the Sea Squirts, and not pro- 

 bably found in any other group of animals. Can it be that 

 human fickle-heartedness has come down to us from our Asci- 

 dian ancestors, with their uncertain cardiac phenomena! The 

 endostyle is interesting, and is a long open canal, glandular and 

 ciliated, with thickened sides, and extending along the ventral 

 face of the cage-like gullet or perforated branchial pharynx. 

 It is active in the digestive functions. The sac-like body has 

 two important openings, one at the top, inhalent, and the other 

 lower down at the side, which is exhalent. A thick coat or 

 tunic loosely encloses the whole animal, whence the name Tuni- 

 cate. This peculiar leathery tunic shows nbrillae, and even 

 cells (mesoderm cells which have wandered from the body of 

 the enclosed animal), but it contains, most wonderful of all, 

 a substance, like the cellulose which is peculiar to plants. Ber- 

 tholet regarded it as a special substance, Tunicin, but recent 

 researches appear to confirm the old and long accepted view 

 that it is really cellulose. Now, cellulose has been regarded as 



