REMARKS UPON APPENDICULARIA AND DOLIOLU.M 75 



MM. Quoyand Gaimard,-' altogether denying the existence of Otto's 

 genus as a distinct form, appropriated his name for two species of 

 tunicate animals observed by them at Amboyna and Vanikoro, and 

 which they justly recognized as being very closely allied to the Salpce. 

 Of these two species, Doliolum denticulatum and Dolioluni caudatum^ 

 the former is the only one with which I have met. 



MM. Quoy and Gaimard give only the following short description : — 

 " Its form is nearly that of the vessel from which we have derived 

 its generic name, that is to say, it is enlarged in the middle and nar- 

 rowed at its two extremities where the openings are situated. The 

 anterior opening is somewhat projecting and denticulated like a 

 crown. Eight circles in relief surround the body at nearly equal 

 distances. They have rather a polygonal than a circular form, and 

 are probably vessels. In the interior the branchia is visible, divided 

 into two portions, which have their oblique lamellae upon a central 

 vessel, as in the Pectinibranchiata. Near the union of the two divi- 

 sions posteriorly is the heart, and between them (?) a vessel, the aorta, 

 ascends ; not far from the heart is a transparent nucleus. This is all 

 that the vivacity of the mollusk, which bounded like an arrow through 

 the water, allowed us to make out of its organization." 



Although I cannot think that MM. Quoy and Gaimard have done 

 well in appropriating Otto's name to an animal confessedly different 

 from that which he describes, it will perhaps cause least confusion to 

 follow their example. 



The specimens which I examined were taken in the South Pacific, 

 a little to the northward of Sydney, N.S.W., between Sydney and New 

 Zealand, and in considerable numbers just at the entrance of the Bay 

 of Islands. 



89. Doliolum denticulatum, figs. 5, 6. — A small transparent body, 

 varying in length from one-sixth to one-third of an inch, and looking- 

 very much like a barrel open at each end, which swims by contracting 

 its whole body, and forcing the water out at one or the other extremity. 



The apertures are considerably less in diameter than the central 

 cavity. The anterior {d) is produced into a sort of tube, with about 

 twelve rounded dentations, which are turned inwards. The base of the 

 tube is surrounded by a thickened muscular rim. 



1 Voyage de I'AstroIabe. Zoologie, t. iii. part 2, p. 599. 



'^ Little more than a description of the outward form is given by MM. Quoy and Gaimard 

 of the Doliolum caudatum, but it strikingly agrees in everything with what one of the 

 associated forms of the singular genus Anchinaia might be supposed to become if set free • 

 •unfortunately, the description of the latter genus itself is very scanty. See note (60), 



Has the Doliolum denticulatum itself been ever an attached form ? From certain appear- 

 ances (90) this appears very possible. 



