96 MR BAIRD ON THE ENTOMOSTRACA OF BERWICKSHIRE. 



his admirable work ; "the wonderful agility of their members; the 

 very great fineness of their organs ; their singular method of living and 

 coi)ulatiug ; their living in waters which our cattle and we ourselves 

 are daily drinking ; the evils which they may give rise to, and to which 

 fishes are seen to be liable ; the emoluments*' Avhich, although we are 

 in the greatest part ignorant of, they nevertheless produce in the 

 economy of nature ; that these things are very worthy of being known, 

 scarce any one will doubt. Not to mention their external similitude 

 to shells and the natural transition which takes place in them from 

 insects to testaceous animals, who ever knew before the Cypris was 

 detected, of an insect quadruped '? f Before the Limulus and Caligus 

 were properly observed, who ever knew of an insect acephalous, or 

 with a head scarcely visible ? Who ever imagined of a copulation of 

 two males and one female at one time, such as takes place in the 

 famous Pulex aquaticus ; or of an animal whose head was all eye, as 

 we see in the Polyphemus ? These and more wonders are to be met 

 with in the history of the Entomostraca."J At commencing this cata- 

 logue, it was my intention to have prefixed some details of each of the 

 genera, as they had come under my own observation, and as they have 

 been made known to us by the continental naturalists ; but I found 

 that, to do justice to the subject, the paper would be swollen to too 

 great a length, and that it would afford abundant materials for several 

 papers which might be communicated at different intervals. I have 

 confined myself, therefore, at present to the catalogue of the Berwick- 

 shire species of the Entomostraca, adding observations on each of the 

 species as they occur. AVe are indebted to the labours of this Club 

 for the knowledge of the fact, that Berwickshire and the district to 

 which our labours extend, abound in a very great variety of species 

 both of the animal and vegetable kingdoms, many of which too are 

 very rare, some scarcely to be found in other counties ; and we also 

 know that the geology of the district is one of very great interest. 

 Sea and land have both been ransacked, and made to give up their 

 hidden treasures, and though the minute and microscopic insects which 

 form the division Entomostraca have hitherto been neglected, I have 

 no doubt that our county and district will yield a plentiful harvest to 

 the gleaner in this department also. Dr Leach, in his article Crusta- 

 cea in the Edinburgh Encyclopaedia, has only enumerated sixteen 

 species of Entomostraca as foiind in Great Britain, a list which is 

 increased by Samouelle, in his British Insects, to twenty. This strik- 

 ingly shews what little attention has been paid to the subject by 

 British naturalists, as I have, in an autumn's search in one district, 

 found thirty-eight species belonging to the order Branchiopoda alone. 



* " It is the common opinion that it is the Caligus which forces the salmon from 

 the sea up rivers towards the cataracts." 



t The Cypris, according to M. Straus, has six feet, two being always concealed 

 within the shell ; according to Ramdohr they have four. 



X MuUer's Entomostraca, p. 4. 



