PARASITIC COPEPODS TAKEN DURING THE THIRD 

 HANCOCK EXPEDITION TO THE GALAPAGOS ISLANDS 



(With One Plate) 



* 



Charles Branch Wilson ' * 



The New England Museum of Natural History, Boston, Massachusetts A 



•<# 7' 



The valuable collections made during the third Hancock Expedi- 

 tion to the Galapagos Islands included the copepods parasitic upon 

 fish. These were gathered not only from the local fish around the 

 islands but also from those captured during the passage to the 

 islands and back. There are thus included among the hosts, fish 

 from the Pacific coasts of Mexico, Central America, Colombia, and 

 Ecuador as well as those from the immediate vicinity of the Gala- 

 pagos Islands. 



The parasites were collected and preserved by Dr. H. W. Man- 

 ter of the University of Nebraska, who accompanied the expedi- 

 tion, and were sent to the author for identification. The host identi- 

 fication is incomplete in one or two instances since the personnel of 

 the expedition did not include an ichthyologist. 



Upon examination the collection of parasitic copepods thus ob- 

 tained has proved to possess peculiar value and interest. This is 

 due chiefly to the exceptional confirmation they aff'ord of species al- 

 ready established but far removed in time, host, or habitat. Practi- 

 cally every one of the species here enumerated contributes new and 

 important information to supplement previous records. This appears 

 in the re-establishment of one species which had been virtually for- 

 gotten, since it had never been reported after its first discovery 75 

 years ago. Two other species almost as old have hitherto included but 

 a single sex, in the one case the male, in the other the female. In both 

 instances the missing sex is here supplied and is described and fig- 

 ured for the first time. Furthermore, these records furnish an abun- 

 dance of new hosts and localities, some of which are very far re- 

 moved from those previously reported. 



With the exception of the two new sexes, whose types have been 

 deposited in the National Museum, all the specimens have been 

 returned to The University of Southern California. For the privilege 



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