1916] The Ottawa Naturalist. 45 



that Steganoblastus is not a blastoid, not even one of the Pro- 

 toblastoidea, as was at first supposed" (1914, p. 202). We 

 must modify this statement. The presence of brachioles should 

 be inferred from the presence of small bordering plates equal 

 in number to the floor-plates, and in zigzag arrangement with 

 them; from the manifest need for additional structures to assist 

 in food capture and respiration; from the appearances noted 

 suggesting hydrospires ; and from the presence of cover-plates 

 nearly as large and solidly fixed as in Blastoidocrinus, which 

 does possess brachioles. The peculiar blastoid-like markings on 

 the channels of the food-grove noted in Edrioaster may be added 

 to this list, for they will probably be found in both Blastoido- 

 crinus and Steganoblastus. Bather goes on to say: "Secondly, 

 the structure of the subvective groove, with its floor-plates and 

 cover-plates, and its pores between the floor-plates, is paralleled 

 by Edrioasteroidea alone among Pelmatozoa, and in that class 

 most closely by Edrioaster, though there are minor differences" 

 (1914, p. 202). This statement cannot stand, for in the points 

 enumerated Steganoblastus is paralleled by Blastoidocrinus, and 

 both plates and pores no doubt functioned in a similar manner. 



We have here a very definite problem to solve, and as we 

 are more likely to find or notice that which first exists in the 

 "mind's eye," a clear comprehension of the problem may lead 

 to an early solution. This idea of a problem-phase in collecting 

 is one we should carefully bear in mind. 



Before closing the present paper a few remarks on "field 

 notes" may not be out of place. It is sometimes desirable to 

 know the position assumed by a form, either while living or 

 during burial. With surface material the determination is 

 easily made. In the case of the holotype of Palaeocrinus 

 striatus Billings, we desired to know whether or not the flatten- 

 ing of the theca was normal. The varying degrees of weather- 

 ing, and the cutting away of the under side to free it from its 

 matrix showed that this specimen was buried with the flattened 

 posterior side down. The bent in condition of that surface may 

 then have been simply due to pressure after burial. (N.Y. State 

 Museum Bulletin 149, p. 216-217). In the Valcour Island 

 specimen of Blastoidocrinus carchariacdens Billings, a knowledge 

 of the side down at death would assist in proving the respiratory 

 function of the hydrospires and the condition of the growing 

 inner edges of their folds, for fine muds were swept into these 

 folds after the stem could no longer support the theca, and 

 before death occurred. (N.Y. State Museum Bulletin 107, p. 

 114, and fig. 2 on p. 105). In Canadacystis emmonsi (Hudson), 

 the rounded, protruding portion of the theca seems to have 

 been an adaptation to secure stable equilibrium on the sea floor 



