LAFOEA. 199 



neous calycles, which are slightly, if at all, pedunculate, 

 differs widely from the forms with which he associated it. 

 To Lamouroux belongs the credit of having first recognized 

 as distinct the type of structure which it exhibits. His 

 Lafoea was founded (in 1812) 011 an American species 

 (L. cornuta} which closely resembles the well-known L. 

 dumosa, and may be identical with it. The genus, how- 

 ever, was lost sight of until, in 1862, it was restored by 

 Sars. In the meantime I had constituted the genus 

 Calicella for the Campanula/rice with tubular calycles, in- 

 cluding under it both the operculated and inoperculated 

 forms. This name, of course, must give way to Lafoea, so 

 far as one section of the group is concerned ; but as I have 

 decided to form the species with an operculum into a sepa- 

 rate genus, I retain it for them. 



It is a remarkable fact that as yet no observations have 

 been made that throw any light on the reproductive history 

 of the present genus. This is the more extraordinary as the 

 species are profusely developed, and L. dumosa is one of the 

 commonest and most widely distributed of the Hydroida. 

 Amongst some thousands of specimens, examined from 

 time to time, I have never met with any trace of repro- 

 ductive bodies. Sars records a similar experience*. 

 Agassiz, indeed, has referred a medusiform zooid observed 

 by his son to the Lafoea cornuta of Lamouroux ; but we 

 learn from A. Agassiz, in his ' Catalogue of North Ameri- 

 can Acalephse/ that this is a mistaken identification. 



Of course, the present definition of the genus Lafoea 

 can only be regarded as provisional. It is quite possible 

 that more than one type may exist amongst the species 

 that are ranged under it. 



* " Beuiaerkninger over firenorske Hydroida," Videnskab. Porhandlinger, 

 1862. 



