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ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 8 



various species I cannot go into a critical valuation of them, and I think it 

 therefore the only fair thing to publish this part of his manuscript as he 

 left it. Future investigations will have to decide about the value of all 



these species. 



One more species, Encope Stokesii L. Agassiz will have to be added to 

 the AVest American species of Encope. Clark gradually became convinced 

 that this species is only the young of micropore, but this is decidedly a mis- 

 take. The internal structure of the test is markedly different from that 

 t}'pical of Encope, the buccal cavity being not closed as it is in Encope but 

 remaining in open connection with intestinal cavity. The subgenus Melli- 

 tella established by Duncan (1889) for this species is therefore fully 

 justified — perhaps it should rather form a genus of its own. 



It is verj' improbable that this species, so fairly common in the warmer 

 region of West American seas, should not be represented in the Velero 

 collections. Specimens of this species have probably been identified by 

 Clark as Encope micropora. A re-examination of his material will be 

 needed for settling this matter. 



Encope (Mellitella) Stokesii will be dealt with fully in the forthcom- 

 ing Vol. IV.2 of my Monograph of the Echinoidea. Th. Mortensen 



The very large number (1,212) of Encopes taken by the Velero in her 

 voyages to the tropical Pacific has necessitated a very detailed and time 

 consuming comparative study of this well-defined and easily recognized 

 genus. It was soon evident that more species of Encope are living on the 

 western coast of tropical America than had been hitherto supposed and 

 that the specific lines drawn needed realignment. In July, 1946, Austin 

 Hobart Clark of the United States National Museum published a "Re- 

 vision of the Pacific Species of the Genus Encope" with the description of a 

 well-marked new species and the recognition of two new subspecies and a 

 new variety. No statement as to the number of specimens available is made 

 but Mr. Clark tells me that both the subspecies are based on "bare white 

 tests devoid of spines." There are very few bare tests in the Velero col- 

 lection and the identification of such tests is a difficult matter, with the 

 possibility of error being very large, unless specimens with spines from the 

 same locality^ accompany them. The hundreds of Encopes available from 

 the Gulf of California show that the Encopes there are either the well- 

 known form here listed as Encope grandis or micropore. It is fruitless to 

 try and recognize either borealis or californica as subspecies or varieties, 

 as they lack any constant association with any locality or any large group 



