3WER SHOAI, HAVEN R1VEK. 213 



Test very thick and strong. Ornamentation concentric, 

 consisting of regular, broad and shallow growth folds. 

 Loc. Burrier(D). 

 Hor. Wandrawandian Series. 



Obs. This species comprises some of the West preserved 

 of all the specimens obtained from Barrier, where it is very 

 numerous. Two very fine testiferous specimens, consist ing 

 of the united valves were found, besides numerous single 

 valves and casts. The general characters of this shell 

 agree very well with the description l»y Munis of his genus 

 I'ttclajtlouius, hut Dana's Astartihi has, according to his 

 own description, a somewhat thinner shell. Other shells 

 belonging to the same group are very abundant at Burrier, 

 but their identification is at present attended with con- 

 siderable difficulty. The fact that many of the original 

 descriptions were taken from very imperfect material, the 

 types of which have either been lost, or are in collections 

 in foreign museums, throws many obstacles in the way of 

 the student. The genus Pachydomus of Morris appears to 

 be a good one, but as to how near Astartila of McCoy 

 approaches this, is very uncertain. 



As the Burrier specimens are especially well preserved, 

 full descriptions are here published for future reference. 

 It must be understood, however, that such a classification 

 is entirely provisional, and the species are chiefly described 

 to aid iu future recognition, and to assist the future eluci- 

 dation of this most difficult group. Moreover, I have less 

 hesitation in leaving this work in abeyance as there is a 

 probability of casts of the types of Dana's work 1 shortly 

 arriving in Sydney, when the group will be revised by 

 Messrs. Etheridge and Dun. 

 Astartila (Pachydomus) sp. (Type B). 



Description.— A small oblique ovate shell, with high, 

 prominent, anteriorly situated umbos; slightly elongated 



1 Geol. of Wilkes' US. Expl. Exped. 



