LYNCEUS AND THE LYNCEIDjE. 105 



and beautifully figured, it belongs to the genus which Loven 

 called Limnetis, and Lievin called Hedessa. Both those names, 

 therefore, are superseded by Miiller's Lyncens, as limited by 

 Leach. As a further consequence the family Limnetidce must 

 yield its name to Lynceidce, which takes rank as a phyllopod 

 family; while in the Cladocera the name Lynceidce must be 

 discarded in favour of a family Chydoridce, Chydorus having 

 been detached earlier than any other Cladoceran genus from 

 that fruitful mother of genera, Miiller's Lynceus. 



Since there is reason to expect that the changes of nomen- 

 clature above introduced will not be greeted with any rapturous 

 enthusiasm by all zoologists, it may be good policy to ward off 

 the "precious balms" of rebuke by evidence that the changes 

 are not unsupported by precedent. In 1865 Sars established 

 a family Lyncodaphnidce, which Lilljeborg still upholds. But 

 already, in 1867, Norman and Brady had substituted for it the 

 name Macr othricidce, with the explanation : " Sars' name for 

 this Family 'Lyncodaphnidse,' not being derived from the typical 

 genus of the Family, in accordance with the usually received 

 rules of nomenclature, we have substituted for it that here 

 employed." It may of course be urged that this was only a 

 youthful delinquency on the part of two authors whose acknow- 

 ledged eminence is of later date. But such an argument will 

 fall very flat in face of the circumstance that G. O. Sars himself, 

 with the openmindness habitual to him, has now accepted the 

 name Macr othricidce, using it prominently in his papers of 1900 

 and 1901 on South American Entomostraca. Some may even 

 now prefer the scholarly emendation Macrotrichidce, long ago 

 proposed by Dr. E. v. Martens in the ' Zoological Record.' 

 The common outcry, that there is no " compensation for dis- 

 turbance " in these rearrangements of nomenclature, is itself 

 very inconsiderate. There can never be any fixity until a settle- 

 ment has been carried out on the thoroughgoing application of 

 sound principle. In the present instance the student of Clado- 

 cera should feel himself in a very happy position. By obedience 

 to law he is involved in nothing worse than the sacrifice of the 

 name Lynceidce in favour of Chydoridce. If he persists in 

 wrongfully retaining Lynceus as a Cladoceran genus, he must 

 sacrifice for it Alona, Baird, instituted in 1843, which has not 



