132 



NATURE 



[March 31, 192 1 



adequate remuneration exists on account of 

 patents not being obtainable for them, or for some 

 other cause, but which has effected or con- 

 tributed to the attainment of any industrial 

 purpose. 



The scheme to which attention is again directed 

 would affect the bestowal of grants in the case of 

 discoveries which, for example, elucidated specified 

 phenomena or solved specific problems. The pro- 

 motion of research by means of rewards, Mr. 

 Priest considers, would also obviate the diflficulties 

 connected with the selection of research workers, 

 their remuneration, the duration of their employ- 

 ment, and their control or supervision. The chief 

 purpose of the scheme is to provide trustworthy 

 means for the administration of grants for reward- 

 ing the discoverers in the subjects specified in the 

 proposed allocation of the grants. Endeavour has 

 been made to provide for all contingencies, such 

 that no earnest student or investigator need 

 despair of receiving pecuniary assistance at a time 

 when it is most needed. 



Mr. Priest is far from sanguine that the 

 methods foreshadowed by the Advisory Council 

 of the Research Department would solve the 

 problems how best to encourage inventors and to 

 assist individual manufacturers who desire assist- 

 ance. He thinks that a procedure which based 

 awards on personal knowledge of the research 

 worker, or of the individual recommending the 

 research worker, is inequitable, and that the 

 methods of promoting research by grants in aid 

 are fundamentally defective. 



The memoranda, which are far too long to be 

 summarised adequately here, may be considered 

 as an advocacy of the system which Mr. Priest 

 has outlined in his draft of a Bill which has 

 for its object the regulation of the allocation of 

 money grants for discoveries in a manner analo- 

 gous to that of grants of letters patent for 

 inventions. 



The Embryology of Crinoids. 



Papers from the Department of Marine Biology 

 of the Carnegie Institution of Washington. 

 Vol. xvi. Studies in the Development of Crin- 

 oids. By Th. Mortensen. (Publication No. 294.) 

 Pp. V + 94 -[- xxviii plates. (Washington : The 

 Carnegie Institution of Washington, 1920.) 

 6 dollars, post free. 



THE early stages in the life-history of recent 

 crinoids have always been regarded with 

 interest, because it was hoped that they would 

 NO. 2683, VOL. 107] 



throw light on the evolution of this class, so rich 

 and various in ancient seas, and on its relation to 

 the other very differently fashioned classes of 

 Echinoderma. Unfortunately, the only forms that 

 have up till now furnished material for the em- 

 bryologist are the unstalked comatulids, or 

 feather-stars, and in the past such material has 

 come from but a single genus, and from only three 

 closely allied species of it — Ante don bifida of our 

 own coasts, A. mediterranea, and A. adriatica^ 

 The accounts of their development by W. B. 

 Carpenter, Bury, Seeliger, and others have shown 

 slight differences, due, in part, probably to 

 specific distinctness of the material. Even if it 

 were not feasible to obtain the early stages of 

 any stalked crinoid, still a study of other species,, 

 representing other genera of comatulids, was 

 much to be desired, since it might then be pos- 

 sible to infer which features were peculiar to 

 Antedon and which were common to comatulids 

 generally, if not to the whole class Crinoidea. 

 Such a study has now been made by Dr. Morten- 

 sen, who has obtained a fairly complete series in 

 four genera, and the pentacrinoid larvae of two 

 others. His results are set forth in clear English 

 with his usual care, and the memoir is illustrated 

 by admirable drawings from his own pencil. His 

 many interesting results are discussed in a 

 "General Part" which demands the attention of 

 professed morphologists. Here we shall select 

 for comment a few observations that bear on the 

 past history of the class. 



The three species of Isometra, Notocrinus, and 

 Thaumatometra from the Antarctic Sea resemble 

 other echinoderms from that region in protecting 

 the brood, Tropiometra carinata, from the coral 

 reefs of Tobago, and Antedon petasus, of the 

 Scandinavian fjords, set their eggs quite free. 

 These two extremes are clearly modifications of 

 the normal plan in which the eggs cluster round 

 the genital openings, and the pentacrinoids attach 

 themselves to some part of the mother or her 

 immediate neighbourhood. This agrees with the 

 colonial habit of many fossil crinoids, in which 

 the roots of the young are frequently attached to 

 the stem of the putative parent. As in echino- 

 derms generally, protection of the brood appears- 

 to involve yolk-laden eggs with meroblastic 

 cleavage ; but the normal egg with less yolk re- 

 tains the regular cleavage. 



In its early days the crinoid larva has no mouth, 

 but in the normal plan the primitive gut 

 (archenteron) curves ventrally to meet the in- 

 vagination (vestibule) into which the mouth after- 

 wards opens. We may infer that there was once 

 a stage in which a larval mouth, opening in that 



