278 EDWARD S. MORSE. 



APPENDIX NOTES ON LIVING Solenomya borealis. 



Since the above observations were made on Solenomya velum, 

 and the matter in type, the opportunity has been given me of 

 studying living specimens of the large species Solenomya borealis. 

 My friend, Major John M. Gould, collected a number of living 

 specimens of various sizes from a young one, measuring 9 mm., 

 to full-grown individuals, measuring 83 mm. These were 

 obtained from dredgings in six to seven fathoms of water by a 

 huge dredging machine engaged in deepening a channel in 

 Portland harbor, Maine. The work of collecting, as may be 

 imagined, was done under desperate conditions. Jumping in 

 between avalanches of mud and water, glancing, raking and 

 jumping out again! In this rapid recorinaisance Mr. Gould 

 observed that the creatures were buried in holes and got the 

 impression that they were buried posterior end downward, the 

 broad, light-colored disk-shaped foot projecting from the holes. 

 This attitude, as before remarked with regard to S. velum, is 

 contrary to the behavior of all lamellibranches that bury them- 

 selves wholly or partially. I am still in doubt about the matter. 

 It is interesting to note, however, that when the creature was 

 placed on coarse material it behaved in precisely the same way 

 as 5. velum. In every case resting on its back it thrust out its 

 foot, raised the anterior end of the body as if endeavoring to 

 thrust the posterior end into the mud. In this connection, it is 

 interesting to observe that the anterior ends of the shells of older 

 specimens were covered with films of slime while the posterior 

 ends were clean and polished. 



In only one instance has the animal been seen to swim or dart 

 through the water though both young and old were specially 

 observed for this behavior. The foot was often thrust out as in 

 S. velum, but not so often nor with such energy. No lateral 

 swing of the foot was observed. The periosteum appeared oily 

 as in S. velum and repelled the water, and Dr. Drew informed 

 me that this feature was so marked in 6". velum that when he 

 dug them from the mud they sometimes floated on the water. 



The character of the siphonal end upon which marked specific 

 differences will be established was quite different from S. velum 

 and it can now be positively stated that 5. velum and 5 1 . borealis 



