NO. 5 RHYNCHONELLOID BRACHIOPODS — COOPER 5 1 



short, receding dental plates ; muscle field large, located anterior to 

 the delthyrial cavity; diductor scars of moderate size, surrounding 

 the large adductor scars ; adjustor scars large ; pallial sinuses sparse, 

 with the vascula media short and branching near midvalve, one 

 branch continuing anteromedially, the other laterally and posteriorly 

 (pi. 21, E, fig. 15). 



Brachial valve interior with small cardinalia having strong and 

 elevated socket ridges, no outer hinge plates and no inner hinge 

 plates ; crura short, of radulifer type, stout, curved ; median septum 

 short, low, and meeting the crural bases at the apex ; diductor at- 

 tachments a pit at the apex. Adductor field small. 



Type species (by original designation). — Rhynchonella squamosa 

 Hutton, Cat. Tertiary Mollusca and Echinodermata of New Zealand, 



P- 37, i873- 



Comparison. — The squamose to spiny ornamentation of this genus 

 makes it one of the most conspicuous of modern and Tertiary shells. 

 The distinctive ornamentation is, however, only one means of dif- 

 ferentiation from other genera. Interior differences also exist in the 

 form of the moderately short crura and apical callosity formed by 

 the crural bases. This and the difference in the pallial markings are 

 means of distinction from Notosaria which is most like Tegulorhyn- 

 chia. 



Geological horizon. — The type species and most other species of 

 Tegulorhynchia are found in the fossil state. The genus ranges from 

 Oligocene into the Recent where it is represented by T. doderleini 

 (Davidson). 



Distribution. — The fossil species occur chiefly in the Southern 

 Hemisphere in the southern part of Australia and New Zealand. 

 One fossil form, identified as T. doderleini occurs in the Pliocene of 

 Okinawa. 



The geographic range of the one living species T. doderleini is 

 from Japan south to Borneo. 



Assigned species. — The species of Tegulorhynchia are : 



Rhynchonella squamosa Hutton, Miocene, New Zealand. 

 R. tubulifera Tate, Miocene, Australia. 

 R. doderleini Davidson, Recent, Japan to Borneo. 

 Hemithyris antipoda Thomson, Miocene, New Zealand. 

 ? H. depressa Thomson, Miocene, New Zealand. 



H. squamosa Buckman (not Hutton), Miocene-Oligocene, Antarctic. 

 H. imbricata Buckman, Miocene-Oligocene, Antarctic. 

 Tegulorhynchia thomsoni Chapman and Crespin, Miocene, Tasmania. 

 T. coelospina Chapman and Crespin, Miocene, Tasmania. 



