CIRRHOPODA. 691 



of the process which forms a kind of caudal were of opinion that these were truly eggs, but 



prolongation of the abdomen (/, '). This held that they were originally formed in the 



canal runs to the distal extremity, and opens granular organ surrounding the intestine, (now 



by a minute orifice fringed with very fine hairs, regarded as the testicle,) and merely deposited 



In Otion Cuvieri the two canals are continued here temporarily. But the recent researches of 



distinct to the very point of the process, where Professor Wagner and M. St. Ange have ren- 



there are two openings.* The walls of the dered it probable that it is the ovary which is 



organ, which we have compared to the seminal contained within the peduncle. The organ in 



vesicle, have a glandular structure, which question seems to occupy the whole of the pe- 



Cuvier imagined to be the testicle. The re- duncle within the layers of muscular tissue, 



searches of Professor Burmeister have led him It is separated from the visceral cavity by a 



to the same conclusion. He says it can be no- fine membrane which lines that cavity, and is a 



thing but the testicle.f Cuvier, as well as reflexion of the mantle. A transverse section 



Lamarck, regarded what we have called the of the ovary shews the eggs most fully deve- 



testicle as the ovary, and believed that the ova loped towards the outer margin, and scarcely 



were impregnated, in the course of their passage formed in the centre. There are also seen in 



along the oviducts, by the seminal fluid flowing the same section two canals which run longitu- 



from the testicle investing these canals. The dinally through the organ, one near that side 



granular lobules of the true testicle, which were of the margin which corresponds to the anterior 



supposed to be immature ova, are found always aspect of the body of the animal, the other in a 



in the same state, and what are more distinctly similar situation on the dorsal aspect. Of these 



ova are found within the peduncle.^ canals, the anterior is the larger ; and it alone 



The lengthened tubular process (t r , t',flg. was described by Cuvier, who regarded it as 



344), through which the excretory duct of the connected with the circulating system. The 



testicle passes, is articulated; the margin of other was first described by M. St. Ange, who 



each joint is fringed with minute hairs. In satisfied himself that it is a true oviduct. In 



Otion and Coronula, Burmeister found large Anatifa, he traced it pursuing a straight course 



canals closed at both extremities, within the through the ovary, and leaving it as a perfect 



process, in addition to the ducts from the testi- canal just at the posterior and inferior angle of 



cle. This organ is generally found after death the organ, thence passing on the outer surface 



bent upwards on the abdominal surface ; but, of the lining of the visceral cavity, in the groove 



during life, it is in continual motion. Its use of the dorsal valve, and terminating in an orifice 



is, probably, to carry the seminal fluid back- opening into the visceral cavity not far from the 



wards beyond the current caused by the move- brachial slit.* We have found a structure 



ments of the arms, in the event of there being exactly resembling the above in Otion, where, 



mutual impregnation between separate indivi- however, instead of opening into the general 



duals ; or towards the mouths of certain ducts cavity of the visceral sac, the duct is bifurcated 



which communicate with the ovary within the just between the two auriform appendages, into 



peduncle, in case of self-impregnation taking each of which one of the branches of the duct 



place. In this view it must be regarded as enters and opens. M. St. Ange found eggs 



the penis; and it is so called by the most in progress through this duct; and they are 



recent authors on the subject Wagner and frequently found, arranged in groups or packets, 



Burmeister. Mr. Thompson calls it an ovipo- two or three in number, within the cavity of 



sitor ; and conjectures that, after their expul- the mantle. We have not yet seen them in the 



sion from the ovary, (understanding by this duct; but the whole structure of the parts in 



what we regard as the testicle,) the eggs are question seems to indicate their adaptation to 



conveyed by it into the cellular texture of the the function assigned to them by M. St. Ange. 



pedicle. How they pass from this depository This being the case with regard to Anatifa, it 



into the general cavity, where they afterwards appears to be very probable that the use of the 



form two or three foliated groups, he confesses singular auriform appendages in Otion is to 



himself unable to explain. afford a convenient lodging for the eggs before 



The peduncle of the Lepads was formerly the young are hatched. Their deep sinuosities 



regarded merely as an organ of support, and and folds seem to adapt them admirably to 



even Cuvier discovered within it nothing but this purpose. Packets of eggs, however, are 



what appeared to him to be a homogeneous found within the cavity of the mantle in this 



pulp, surrounded by muscular tissue. But, at species as in others. According to Burmeister, 



certain seasons of the year, at least, there are, these packets are unattached, excepting in the 



very distinctly developed, throughout the greater earliest stage of development ; but Wagner has 



part of the soft matter which constitutes the generally found them fixed to a process of the 



bulk of the organ contained within the dense mantle, situated near the adductor muscle of 

 cartilaginous and muscular tunics, certain oval 



granules, regular, and uniform in shape, and Professor Wagnrr says "at the base of the 



T} ,. , ,' dorsal valve there exists a slit in the mantle which 



gradually increasing in size. Poll and Lamarck , eads into the cana , that runs through the peduncle. 



I presume that this canal serves as an oviduct, and 



* Burmeister, Bcitrage, p. 46. that the slit is analogous to the opening of the 



t Op. cit. p. 44. branchial canal in the bivalves," (in Archiv flir 



{: Professor Wagner is satisfied that nothing but Anat. Physiol. &c. von D. J. Miillcr, 1834, No. 5, 



the discovery of spermatic animalcules can assure quoted in Ann. des Sc. Nat. iv. n. s.) We are not 



us against error in our attempts to determine what aware what species was auatonii/cd by Professor 



is the testicle. Wagner. 



