214 DE. T. DAVIDSON ON EECENT BEACHIOPODA. 



straight portion of tlie intestine corresponds to the entire intestine of the articulated 

 Brachiopods, and it thus appears that in Llngida, as well as in them, the first inflection 

 of the intestinal tube is towards the ventral surface. From thence the tube bends to 

 the left, and turning forwards and upwards, forms two large loops at the posterior 

 portion of the perivisceral chamber ; it then advances along the right side, and, dipping 

 under the dorsal extremities of the adjuster muscles and the pseudo-heart, opens through a 

 nipple-like anus situated at the right side of the body between the margins of the mantle. 

 The anal orifice is ample, and is very easily distinguished ; it is placed considerably nearer 



to the dorsal than the ventral surface The liver is composed of ramified caeca, and 



is of a greenish colour, as in all the Brachiopods " (p. 816). 



Hancock then describes the reproductive organs, which, he states, are really developed 

 between the two layers composing the ilio-parietal bands. He adds that the reddish-yellow 

 marks are the ovaries, and that it would be fair to conclude that Lingula, at least, is andro- 

 gynous ; and if the red matter in connection with the genitalia in the articulated 

 Brachiopoda should jirove to be the same as the dendritic organ of the former, then in 

 them also the sexes are combined (p. 819, loc. cit.) *. 



The ova of Lingula anatina were figured in Prof. Owen's memoir on the anatomy of the 

 Terehratulce appended to the Introduction to my monograph of British Fossil Brachiopoda. 



The peduncle in Lingula anatina attains a very great length, and has been minutely 

 described by the zoologists already named. Drs. Vogt and Gratiolet state that it is com- 

 posed of two essential parts — (1) a horny envelope, (2) a central muscular mass. The 

 external envelope is very thick, resisting, and constitutes a tube open at both ends. The 

 opening of the lower end is gaping, that of the other end, perforated in the centre of the 

 inflated portion, is very narrow, and affords passage to small muscular bundles. It is 

 remarkable how very much this peduncle shrinks and shrivels up when in the dried 

 condition. In an abstract of Prof. Morse's paper on Japanese LlngulcB and shell-mounds, 

 published in the ' American Journal of Science and Arts,' vol. xv. 1878, it is stated that his 

 studies of L'mgtda. have brought out many points new to science. The discovery of auditory 

 capsules in the class of Brachiopods is one of the most impoi-tant. These organs he 

 determined in a species of Lingula, and their position and general appearance recall the 

 auditory capsules as figured by Claparede in certain tubicolous Annelids f. He has also 

 cleared up many of the obscure points in regard to the circulation, and is prepared to 

 maintain the absence of anything like a pulsatory organ, the circulation being entirely 

 due to ciliary action. Prof. Morse also described some of the habits of Lingula. "While 

 partially buried in the sand the anterior border of the pallial membranes contract in 

 such a way as to leave three large oval openings, one in the centre and one on each 

 side. The bristles, which are quite long in this region of the animal, are arranged 

 in such a way as to continue these openings into funnels, and entangle the mucus which 

 escapes from the animal ; these funnels have firm walls. A continual current is seen 



* [The recent investigations of Dr. H. G. Beyer fully confirm Hancock's views as to the hermaphroditism of 

 Lingula {GloUkUa) pyramidata. See Note p. 238. — A. C] 



t Dr. W. K. Brooks states at p. 63 of his paper on "The Development of Lmgida " (Results of the Chesapeake 

 Zoological Laboratory, 1S7S), that these octocysts do not exhibit any annelidan characteristics: they are precisely 

 such structures as are found in most of the Mollusca. 



