OF SOUTHEFX IXDIA. 
wliicli is the strongest, and has the function of Icecping the valves closed ; it is 
dorsally divided into four hranches, producing two anterior, larger and stronger, and two 
posterior, smaller and weaker, sears ; ventrally it is nearly united, producing an 
elongately ovate scar, sometimes divided ])y a sliglit median swelling of the shell or 
hy a distinct rih. The 2nd arc the cardinal muscles, of which there is an anterior 
and a posterior (or accessory) pair. Tlic fu-st is attached near the umbo of the hsemal 
valve, and on either of the anterior sides of the adductor scar in the neimal valve. 
This cardinal muscle, usually also called divaricator, has as its principal object 
the opening of the v'ah^cs. The so-called divaricator accessorius is also attached on 
the hinge plate of the haemal, and posteriorly on the neural, valve ; it is much thin- 
ner than the former. The 3rd set are the so-called adjuslatores, which are intimately 
connected with the 4th large muscle, or the peduncle; the adjuslatores are chiefly in- 
tended as erectors or retractors of the peduncle, and are, therefore, obsolete or nearly 
so in those species which do not possess the latter. 
A very current idea exists, that the Braehiopods fix themselves permanently hy 
then’ peduncular muscle to suh-marine objects, hut tliis is, I think, highly improbable. 
From what I saw of recent Lingula;, I am inclined to believe that they arc capable 
of changing their place actually hy the movements of the pcdrmele, and probably 
they also swim through the water by opening and closing their valves. I found 
Lingula anatina on tho Arrakan Coast a little below tide-mark, and many other 
Terehratulce, Orhiculce, and others, are known to live in similar places ; the majority 
of the large recent forms indeed arc probably littoral, but some also occur at con- 
siderable depth, and others only in deep water. 
There can not be, I think, much doubt as to the true molluscous character of 
the Bracliiopoda, and them proper classification between the Anomiidee of the 
Pelecvpoda, the Saccopoda, and the arm-bearing section of the Clliopoda. M r . 31 o r s e ’ s 
rather startling idea that all the Brachiopoda and Ciliopoda should be classed with the 
Annelids, instead of forming the lower division of the 3IoUusca, is, therefore, not 
likely to obtain much valid support. Its bearings upon classification have been 
lately ably discussed by 3Ir. Dali in Am. Journ. of Conehology, vol. vi, pp. 88, &c.* 
I quite agree with that author’s conclusions, that 3Ir. 3Iorsc has come to his conclu- 
sions on inadequate grounds. It would not be diffieidt to point out more characters, 
than 31 r. Dali has noticed, which speak in favor of the now generally adopted idea 
of the classification of the Brachiopoda. Indeed it seems to me that the difierences 
between the internal organs of the Pclccypods and of the Braehiopods arc not so 
enormously great, as is generally supposed. The division of the mantle is no doubt 
essentially dificrent, being lateral in the former and dorso-ventral in the latter, 
and according to this of course all the other organs change. The arms must 
be looked upon morphologically as the homologues of the labial palpes, 
but in the Braehiopods they also receive the function of respiration, tho true 
branc h in . have become entirely obsolete. The adductors correspond to the same 
* And again in Am. Jour. Conch., vol. vii, p. 39 et scq^. 
B 
