428 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 45. 



sideration goes a long way in the direction of alleviation of this regret. 

 No amount of accurate work on the specimens that come into one's 

 hands can make up for deficiencies in the collections themselves. 

 Deficiencies in collections are usually of three sorts, mainly: Insuffi- 

 ciency of number of individuals; insufficiency of representation o'f 

 the various parts of the geographic range, horizontal and vertical, of 

 the groups; and poorness of preservation of the specimens. Inade- 

 quacy of locafity and other incidental data is also not infrequent, but 

 on the whole this is less serious according to my experience than the 

 other items mentioned, especially as concerns collections made in later 

 years. The collection is very rich in number of individuals of some 

 of the species; but in no case is the distribution of these individuals 

 with respect to the geographic range of the species what one would 

 lil^e to have it. Again, several of the species, even some of those 

 treated as new to science, are represented by only one or a very few 

 individuals. This is unfortunate. On the whole, the state of pres- 

 ervation of the specimens is better than might have been expected 

 considering the conditions under which the collecting was done. 

 Special reference ought to be made, I feel, to the extent to which the 

 value of the collection is due to the work as a collector done by Dr. 

 W. H. DaU in the early seventies of the last century, when Alaska 

 was hardly more than a map to most persons in the United States. 

 The services of Doctor DaU in this connection are notable in view 

 of the adverse conditions under which his natural history work was 

 carried on. 



The part played by the United States Fisheries Bureau steamer 

 Albatross in gathering material is dealt with in a special section. 



I am glad to acknowledge the helpfulness of the officials of the 

 United States National Museum, particularly in granting small sums 

 of money to aid m the work and also for the efficiency and patience 

 of Dr. Myrtle E. Johnson in making dissections, rough sketches, and 

 finished illustrations. 



Although a considerable number of papers, old and new, now exist 

 dealing with the ascidians of the north Pacific, the recent extensive 

 summarization not only of these but of the literature of the whole 

 group given by Hartmeyer in his Tunicata of Bronn's Tierreich, 

 makes a general review of the work to which reference is made in this 

 report unnecessary. No student would presume to work seriously on 

 ascidians from any part of the world now or for many years to come 

 Avithout Hartmeyer's writings constantly at hand; and with these it 

 would hardly be possible for him to miss altogether any of the litera- 

 ture with which he should be concerned. It is a great pleasure to 

 me to speak of the comprehensiveness and accuracy with which 

 Hartmeyer has done his work, and I genuinely regret that in a few 

 important matters I am unable to follow him, at least for the pres- 

 ent. To the very recent paper by Huntsman, 1911, dealing with 

 the ascidians of the Canadian coasts, Pacific as weU as Atlantic, 

 ample reference is made in other connections. 



