[ 70 J 



favour of the opinion that the class should be considered to 

 constitiite a distinct group among the Molluseoidea. 



fiANGES OF DEPTH. 



All Brachiopoda wei-e inhabitants of the sea, and had been met 

 with at depths ranging from less than a foot tu that of 2,fi00 fathoms, 

 between Kerpules Island and Melbourne. (Her Majesty's Challenger 

 expedition). Some Lingulae lived partly buried in mud; whUe Pro- 

 fessor Morse described a species of the genus which he found in 

 vast numbei's " in a sand shoal at low water mark buried just 

 below the surface of the sand. The peduncle, six times the length 

 of the shell, was partly encased in a sand tuhe diifering in no 

 respect from the sand tubes of neighbouring annelids. He 

 observed (likewise) that Lingnla jjijramidala had the power of 

 moving over the sand by the sliding motion of the two valves, using 

 at the same time the fringes of setae, which swung promptly back 

 and forth like a galley of oars, leaving a peculiar track in the sand. 

 In the motion of the setaj he noticed the impulse commencing from 

 behind and running forward. The larger number of species lived, 

 however, at depths from five to thi'ee or four hundred fathoms, 

 some apparently in the free condition, others attached by their 

 peduncle to various marine objects, and very often to coi-al reefs. 

 Discina had been found attached to stone at low water, and been 

 dredged from depths ranging from five to neai'ly 2,000 fathoms 

 (Discina atlantica). Mr. Jeffreys did not believe tliat the habitat 

 of any invertebrate animal was affected by bathymetrical conditions. 

 Jukes got any number of ]Valdheii)na flavescens while ))oating in 

 Australia among the reefs, they were merely washed by the tide, 

 and he gathered them with his hand like limpets on the shore. 

 Certain minute forms were found by Mr Jeffreys fixed to seaweeds, 

 while others adhered by a lai-ger or smaller portion of one of their 

 valves to submarine rocki?, stones, corals, &c. 



CLASSIFICATION. 



It would not be possil^le on so brief a piper to enter at any 

 length on the subject relating to the classification of the Brachiopoda. 

 This important matter would be found fully discussed up to the 

 year 1853 in the geuei-al introduction to his great work on " British 

 Fossil Brachiopoda." He then published his own views, and which 



