258 On some Brachiopoda found on the Coast of Norway. 



Terebratulina caput- 

 serpentis. 



itself than any other, and protrudes its cirri further ; it was met 

 with everywhere, in small numbers, in 30 to 150 fathoms, often 

 attached to Oculina. The cirri on the reflected part of the arms 

 are shorter than those on the first part, as shown in the wood- 

 cut. The cirri were almost constantly in motion, and often ob- 

 served to convey small particles to the channel at their base. 

 When placed in a small glass of sea water the valves gradually 

 opened. Individuals remaining attached to other objects mani- 

 fested a remarkable power and disposition 

 to move on their pedicles. Detached speci- 

 mens could be moved about without causing 

 the animal to close its valves. If any of the 

 protruded cirri were touched, the cirri were 

 retracted and the valves closed with a snap, 

 but soon after opened again. When the 

 oral arms are retracted the cirri are bent up, 

 but are gradually uncoiled and straightened 

 when the shell is opened, before which the 

 animal has often been observed to protrude 

 a few of its cirri and move them about, as if to ascertain if any 

 danger threatened. Only on one occasion a current was observed 

 to set in on one side between the two rows of cirri. I had 

 been attempting to ascertain the existence of currents, by in- 

 troducing small quantities of indigo into the water surrounding 

 the animal with a camel*s-hair brush; three times the water 

 was forcibly drawn in, and particles of indigo were seen to 

 glide along the groove at the base of the cirri in the direction 

 of the mouth. 



2. Waldheimia cranium occurred on several occasions between 

 Vigten Islands and the North Cape, in 25 to 150 fathoms, at- 

 tached to stones, Balani, &c. ; only once in plenty at Omnsesoe. 

 This species belongs to the division of Terebratulidse with a long- 

 loop, and the oral arms are so fixed to the calcareous ske- 

 leton as to be incapable of motion, except at their spiral ter- 

 minations : it has been supposed that these conjoined spiral 

 ends could be unrolled, like the pro- 

 boscis of a butterfly ; but I never saw 

 any disposition of the kind manifested. 

 This species is more lively than caput- 

 serpentis, moving often on its pedicle, 

 also more easily alarmed ; the cirri are 

 not protruded beyond the margins of 

 the valves ; when the shell is closed 

 they are bent up. No currents were detected, though fre- 

 quently sought for. 



Waldheimia cranium. 



