OF CONCHOLOGY. 55 



chiopods, and the second is erroneous. All of the Scolecida and 

 some Annelids are without setae, which are not characters of class 

 value, and are absent ill many Biachiopods, as before bhown. 

 Nevertheless the presence of* setae may be allowed to be indica- 

 tive of faint articulate affinities, as in the case of Chiton. 



6. Setce of Brachiopods moved freely by the animal, and 

 identical in structure with those of the worms. 



The first statement needs confirmation, and at any rate can 

 refer to -very few Brachiopods, and I have already proved that 

 they are far from being identical with those of the Annelids. 

 Neither do they bear the same position with regard to the other 

 parts as in the worms. 



7. Resemblance between the lophophore of Brachiopods and 

 a similar structure in the tubicolous worms. 



This resemblance is very distant, and the structure is totally 

 dissimilar. The homology between the anterior segments of 

 Sabella and the mantle of Brachiopods, which follows, is super- 

 ficial and erroneous to an extraordinary degree, as any one who 

 will take the trouble to look at the two structures may readily 

 perceive. The organization of the two animals is so utterly 

 different that any such homology is impossible. 



8. Thin and muscular visceral ivalls suggest similar parts in 

 the ivorms. 



This is obscure, and it is impossible to say whether it refers to 

 the walls of the viscera or of the visceral cavity. Those of the 

 viscera in Brachiopods are anything but thin, and it is difficult 

 to see the bearing of the observation in any case, as the charac- 

 ter of the visceral walls is of no systematic importance. 



9. Lamelloe on the internal surface of the mantle in Balanus 

 and Lingula. 



The discovery of branchial lamellae on the mantle of Glottidia, 

 discovered by Prof. Morse, is exceedingly interesting and a 

 valuable contribution to our knowledge of the group. It remains, 

 however, to be seen whether it also occurs in Lingula proper. 

 As to its homologies, they may as well be sought in the Patel- 

 lidfe and Siphonariido3 as among the Cirrhipedes. With regard 

 to the position of the ovaries in the latter and in the Brachio- 

 pods, the homology needs confirmation, and the fact is of very 

 doubtful importance in classification, especially when we remem- 

 ber the varied position of the ovary in the true mollusks. 



