INTIIODUCTION. 
Tlie Bvacliiopoda in tlie cretaceous deposits of the Trichinopoly and South 
Arcot districts of Southern India arc not nearly so numerous as are the three other 
classes of Mollusca — Cephalopoda, Gastropoda, and Pelccypoda — which have been 
dealt with in the previous volumes of the Pakeontologia Indica. This smaller 
number of species miglit have been naturally expected, for although the Braehiopoda 
often abound in the number of specimens in the younger mesozoic strata, the number 
of generic and specific forms docs not more than approach that of tlie other 
classes of Mollusca. 
llegarding the classification of the Braehiopoda and their allies,* in several 
important anatomical points, as well as regarding the system of nomenclatiu’c and 
other similar details, I have already spoken in my introductory notices to the 
other classes of the IMollusca, and it will, therefore, not be requisite to repeat those 
statements in this place. Neither will it be necessary in the examination of the 
South Indian cretaceous Braebiopoda to enter into those details of general classi- 
fication which it has been deemed advisable to iilace on record, when irorking 
out the three other classes of Mollusca, The comjiarativcly early publication of 
such a splendid handbook as that on the “ Classification of Braehio])oda ” hy 
Thomas Davidson, Esq., and the translations of the work into Ereneh by 
Deslongchamps, and into German by Prof. Su ess, fully account for this. APe 
have also an excellent account of this class hy Broun in his “ Klasscn und 
Ordnungen dcs Thierreiehes,” and several authors have added to our knowledge 
of it since the publication of the last named work. 
A third point to which I paid particular attention in the other classes of the 
Atollusca was to give, as far as possible, a complete list of the species of each 
class, as represented in cretaceous dcpo.sits in general. This important resume had 
been initiated by Pictet in his famous “Matcriaux pour la Palcoiitologie Suisse.” 
And as the lists of the cretaceous species of (he three ])rcccding classes of Alollusca 
* Saccopoda or Tunkata, and Ciliopoda or IJiyozoa. 
