Miscellaneous. 73 



radons with which the shell is pierced. These facts establish a 

 characteristic difference between the Terebratidce and the Lamelli- 

 branchiate Mollusca, and justify the denomination of Palliobranchiata 

 which has been bestowed upon the Brachiopoda. 



3. The arms. — The large stiff canal which serves as their base is 

 in communication with the cavity of the body, but it has no con- 

 nexion with the capdlary tubes of the fringes. These tubes are con- 

 nected with deUcate canals which run beneath the base of the fringes, 

 and by means of which the erection of the tabular threads is pro- 

 duced. The organization of these arms does not justify our attri- 

 buting to them very extended movements, which, moreover, agrees 

 with the direct observations of Quoy and Gaimard. The author 

 fomid no traces in this animal of the retractor muscle of the arm so 

 apparent in the Orbiculce and Lingulce. 



4. Digestive apparatus. — The mouth is a small opening bordered 

 on one side by the fringe of the arms, and on the other by a small lip 

 which is not ciliated, and which is continued on each side through 

 the whole length of the fringe as far as the extremity of the median 

 arm. ITie anus does not open upon the side of the animal, as has 

 been stated, but on the middle near the bottom of the perforated 

 valve. 



5. Vascular system. — The large venous sinuses of the body send 

 off long processes (four to each lobe of the mantle). These processes 

 fmuish no vessels of any kind to the iimer surface of the mantle ; 

 they ramify exclusively in its margin. From this marginal plexus 

 the vascular ramifications which form the branchial network of the 

 outer lamina originate. The branchial veins which collect the blood 

 from this network carry it to the auricle of the two hearts ; this 

 auricle does not open into the sinuses of the cavity of the body, as has 

 been stated ; it is exclusively branchial, as is the case in all MoUusca. 



6. Nervous system. — The centre of the nervous system of Tei-e- 

 bruiula australis consists of a quadrilateral collar which surrounds 

 the oesophagus. The side of the collar which is beneath the fringed 

 lip is the thickest. From the angles arise long nerves which ramify 

 in the paUial lobes, and especially m the margin. The author could 

 not perceive the nerves of the arms. The same structure is found in 

 Liiiyula. 



7. Generative apparatus. — The male and female organs are not 

 mingled with the granulations of the liver, as has been stated from 

 analogy with what exists in Orbicula and Lingula. They consist of 

 small caeca attached in great numbers to a sort of mesenterv', and 

 float in the interior of the pallial venous sinuses. The author sup- 

 poses that the ova of the females and the seminal fluid of the males 

 escape by canals opened on the inner surface of the mantle. — Comptes 

 RenJiis, July II, 1853, p. 45. 



ON THE TEETH OF PERONIA AND OTINA. 



In the ' Annals' for November 1853, I described the teeth of the 

 genus Peronia as exactly similar to those of Testacellus ; they were 

 described from a shde mounted by Mr. Wilton, shown to me bv 



