362 MEMOIR ON PHYSALIA 



Of the function of the stomachal sacs in receiving the prey there can 

 be Httle question ; but it may be doubted whether the digested nutri- 

 tive matter circulates in the ciliated water-carrying canals or is 

 absorbed into totally different channels. In the latter case the pur- 

 pose of the stomachal villi would plainly seem to be to absorb nutri- 

 tive matter and convey it through their central canal to the wide 

 interspace existing between the outer and inner membrane ; but the 

 author states that he has never seen in this interspace any corpuscles 

 analogous to those described by Will as blood-corpuscles. He 

 suggests that the villosities noticed by Dr. Milne-Edwards in the 

 stomachal sacs of Apoleinia are the same organs, and not ovaries as 

 Dr. Milne-Edwards considers them ; and observes that similar organs 

 exist in a Diphya {Eudoxia), hereafter to be more fully described- 

 The function of the tentacles, both as prehensile and defensive organs, 

 admits of little doubt ; and on this subject the author notices an 

 erroneous view of M. Lesson, who describes them merely as ducts for 

 conveying an (hypothetical) acrid fluid from an (hypothetical) poison- 

 gland. He also controverts M. Lesson's opinion that certain of the 

 colourless tentacles are to be regarded as branchia; ; being quite con- 

 vinced that there is no difference between these and the ordinary 

 tentacles except in the absence of colour. i\s regards the function of 

 the cyathiform bodies, he has no other than analogical evidence to 

 offer. The only organs in the AcalephcE\\'\\h which he conceives them 

 to have any resemblance are the natatorial organs of the Physophoi'ce. 

 But their little adaptation to a similar purpose, and the entire absence 

 e\'en of their rudiments in young PIiysali(E, discourage this com- 

 parison ; while on the other hand they bear a singular resemblance to 

 the female generative organs of a Diphya, and this resemblance extends 

 even to the younger stages of both. 



Mr. Huxley concludes by referring Physalia to the position as- 

 signed to it by Eschscholtz among Physophorce, and near Discolabe or 

 Angela. In fact, he regards Physalia as in all its essential elements 

 nothing but a Physophora, whose terminal dilatation has increased at 

 the expense of the rest of the stem, and hence carries all its organs at 

 the base of this dilatation. 



The paper was illustrated by pencil drawings of the structures 

 described. 



