THE NAUTILUS. 39 



Twelve specimens of Axtyris htnntu from Wood Hole, Mass, 

 weighed 0.095 gms. This would make one specimen weigh about 

 <l.( IDS gm. Reducing this to avoirdupois weight we have one shell 

 weighing 0.000282 oz. 



The next example is Cerithiopsis Greenii being the first of the 

 species found in Canadian waters, i. e. from Prince Edwards Island. 

 Ten specimens weighed 0.023 gin. or in ounces one specimen would 

 weigh 0.000081 oz. 



Two sets of Odostomia semimtda were compared. The one being, 

 like the above, the first found at Prince Edwards Island. The 

 others came from near Woods Hole, Mass. It was found that the 

 ( 'unadians weighed each 0.000048 oz. while those from Mass, weighed 

 each 0.000105 oz. The difference in size is noticeable without 

 weighing. This proves that Mass, is a better place to live than 

 Prince Edwards Island. The most interesting of all is New Eng- 

 land's conchological elephant, Skenea planorbw. The set weighed 

 was found near Saco, Me. The average weight of a specimen is 

 O.OOI>018 oz. At this rate it would require 56,700 to make an ounce, 

 907,200 to the pound, and a ton would require 18,144,000,000. At 

 the rate of five cents each, a pound would be worth $45,360.00. I 

 am sorry to say I cannot supply them by the ton, or pound. 



After weighing, the writer became interested in size comparisons, 

 and two species from the same region, i. e. Saco, were compared. 

 The largest shell in my New England cabinet is Maetra, solidissima, 

 and the smallest Skenea planorbw. The Mactra weighs 17i oz. It 

 would require 1,004,250 of Skenea to balance the one Mactra. The 

 surface of the Mactra was reduced to a flat as near as possible, 

 divided into small squares, and the Skenea was placed on the small 

 square to estimate the comparative size. Dividing an inch into 

 sixteen squares, Skenea would find room enough for 25 on each 

 square, or 405 to the square inch. On the total surface of the 

 Mactra (including both sides) there would be space enough for 

 30,000 individuals of Skenea to rest comfortably. The above species 

 are all marines and hence the comparisons are more interesting 

 since conditions of life are similar. Much larger forms occur in other 

 waters but the specimens selected represent the extremes of the New 

 England area. I need hardly say that in commercial life these 

 -extremes are avoided and the medium sizes are of more economic 

 value and popularity. 



