Mr. Patterson on the Cydippe Pomi/ormis. 93 



From each side of the vesicle, near its connexion with the central vessel, there 

 arose a tube, which after dividing, sent a branch to each contiguous rib. The 

 cavity of these tubes, at their union with the ribs, appeared to be filled with a 

 whitish coloured pulp. Each rib is furnished with a tube uniting with it near 

 the middle. In consequence of this peculiar structure, I could easily observe 

 the water enter the tube at the summit, pass into the lateral vesicles, and go out 

 at their external openings ; and in some cases the motion of the current was 

 reversed." 



On the 10th of June, 1838, I had an opportunity, for the first time, of 

 examining, under a lens, one of the Beroes exhibiting the peculiar ramiform 

 structure already noticed. The animal was lying, like that observed by Dr. 

 Fleming, with the mouth downwards, and evidently in an exhausted state. To 

 my great satisfaction I observed the particles of fluid in motion, nearly in the manner 

 that author has described, and in the vessels close to the stomach could observe 

 there were two currents flowing In opposite directions. The same was visible in the 

 whitish coloured vessels, going out to the bands of cilia. It was not apparent in 

 the " lateral vesicles," they were filled with water, which moved at times back- 

 wards and forwards, but did not exhibit the active and continuous current pre- 

 sented by the other parts. That water issued from them was, however, obvious, 

 by the effect visible on the fluid adjoining the terminal aperture, and exterior to 

 the body of the animal. While examining one of the " glandular" bodies, I 

 noticed that it did not always retain the same appearance, but was capable of 

 expansion and contraction, and that on one occasion it was extended almost to 

 the surface of the animal, moving within one of the " lateral vesicles," and ap- 

 proaching its external orifice. I waited in hopes that both of these " glandular" 

 bodies would be still more fully thrown out, and would prove to be tentacula ; 

 but the inertness of the animal prevented at that time the fulfilment of my 

 expectation. Next morning another Beroe was taken, vigorous and perfectly 

 uninjured, and with the whitish ramiform vessels equally conspicuous as in the 

 previous specimen. In the course of a few minutes it unfolded to my view its 

 graceful and ever varying tentacula, furnished with delicate filaments, and exhi- 

 biting a ceaseless variety of outline. 



The presence of the tentacula removes the animal from the genus Beroe of 

 Fleming to the Pleurobrachia of the same author. His Inaccuracy in the present 



