46 The Ottawa Naturalist. June-July 



with arms and mouth uppermost. Most specimens of Malo- 

 cystites when rolled on a table come to rest with the food- 

 collecting field uppermost. That the theca in this species rested 

 on the bottom is shown by the area over which arm extension 

 did not take place, and in this portion of the theca the plates 

 were the heavier, thus lowering the center of mass and securing 

 stable equilibrium with this part down. Dr. Foerste (1914) 

 believes that the slope of the bed or surface of attachment in- 

 fluences not only the form of the theca, in Agelacrinus, but also 

 the bending of the rays; and Bather (1915, Geological Magazine, 

 p. 261) says: "Here, as in so many similar cases, the field col- 

 lector and observers have not supplied the laboratory worker 

 with the desired evidence." Not only has gravity left many 

 an unread story of its influence, but even orientation has some 

 important new items for us; for instance, see Patten, 1912 

 (Evolution of the Vertebrates) p. 377-3 79, and fig. 2 57, where 

 much of the "mode of life" of Bothriolepsis is determined from 

 the position of the remains of this genus as preserved in the 

 beds near Dalhousie, New Brunswick. Orientation may also 

 have much to tell the paleogeographer as to direction of stream 

 flow and of tidal currents. It would be a very easy matter to 

 mark collected material in the field with an arrow in its under 

 surface, indicating north. There seems to be room yet for 

 improvement in our purpose in going afield, in our judgment 

 of the character of the material saved, in our marking the 

 specimens when found, and in the character of our field notes. 

 We must also bear in mind that there is much to be saved and 

 gained through any guiding care or assistance we may give to 

 those lovers of nature who belong to the generations that are 

 following ours. 



NOTE. 



Mr. J. H. Emerton, of Boston, Mass., spider specialist, 

 recently visited Ottawa and other points for the purpose of 

 collecting spiders. During his stay in Canada he obtained a 

 large number of different species, the collection of some of 

 which extended the known range of distribution. Mr. Emerton 

 is making a special study of Canadian spiders. Members of the 

 Club interested in entomology could assist materially in such 

 study by sending specimens from their immediate districts. 

 If preferable, the Editor of The Ottawa Naturalist would 

 be glad to forward any material sent to him. 



