20 C. McLEAN TEASER 



series of joints, seem to be arranged in fairly definite rows, but 

 more commonly there seems to be no regularity in their arrange- 

 ment; they are simply scattered over the hydranth surface. In 

 the young forms they may be very few in number but as de- 

 velopment proceeds the number is increased, until as many as 

 24 may be present. 



Gonosome. — Gonophores, from 1 to 3, are developed a short 

 distance below the tentacles. From each of these a single medusa 

 with 4 marginal tentacles is developed. 



Distribution. — Departure Bay. 



I am indebted to Dr. A. G. Huntsman for the pleasure of 

 studying this rather unique species. It is found in the branchial 

 basket of several species of simple Ascidians, dredged from 5 to 

 20 fathoms and if it had not been that Dr. Huntsman was dis- 

 secting one of these Ascidians while I was studying hydroids 

 near him, I should never have come across the species. After he 

 handed over the first specimens I was able to procure a good 

 supply, as the Ascidians were common and many of them were 

 hydroid hosts. Though it is a common occurrence to find 

 hydroids growing on the surface of ascidians, ordinarily one 

 Avould scarce think of looking for specimens inside. It is evident 

 that such a position is not accidental when the majority of the 

 ascidians possess at least a few hydranths. The hydroids must 

 thrive well in such a habitation, as presumably they get their 

 food from the water current in the branchial basket without re- 

 ceiving any detrimental effect from their position. In two or 

 three cases, instead of these hydroids, I found free-swimming 

 copepods, females with egg-sacs turgid with eggs. It may be 

 that these copepods were in the same locality for the purpose of 

 using the hydroids as food, but there was no direct evidence that 

 such was the case. 



It seemed a very easy matter to find all the developmental 

 stages of the hydroid until the period was reached for the forma- 

 tion of the gonophores but there were not many specimens with 

 these present. As I saw no free medusa I can only surmise 

 that the radial canals are as those in other genera of the Family. 

 There is no doubt as to the four marginal tentacles as in some 

 cases these were plainly visible. In its generic characters there 

 are rather distinct differences from other genera of the Family, 

 yet the resemblances seem sufficient to retain the genus in the 

 Family Turridse. 



