316 On Lar sabellarum and its Reproduction. 



the name of the family. LaridcB (which would be the natural 

 designation, and which I have adopted in my ' History ') has 

 been appropriated by the ornithologists ; and Allman proposes 

 to substitute for it the compound Hydrolaridm. I confess that 

 I have serious doubts as to the expediency of this change. It 

 seems to me that no practical inconvenience of any moment is 

 likely to arise from the identity of the two family names, under 

 the circumstances of the case ; while there is a positive dis- 

 advantage in the adoption of a term which does not at once 

 suggest the typical genus. The rules respecting zoological 

 nomenclature have been framed with a view to general con- 

 venience, but are not to be inflexibly applied without regard 

 to special circumstances. In the present case I should feel in- 

 clined to retain the name Laridce'^. 



The following is the amended diagnosis of the genus Lar, 

 and of the only known species. 



Subkingdom GCELENTERATA. 



Order HYDROIDA. 



Suborder ATHECATA, Hincks. 



Fam. LaridsB. 



Genus Lar, Gosse. 



Polypites fusiform, developed on a creeping filiform stolon 

 clothed with a polypary ; tentacles two, filiform, springing from 

 one side of the base of a bilabiate proboscis, which is separated 

 by a constriction from the rest of the body. Reproduction by 

 means of medusiform planoblasts, which are borne on im- 

 perfectly developed polypites (blastostyles), terminating above 

 in a spherical cluster of thread-cells. 



GONOZOOID : umbrella (at the time of liberation) subhemi- 

 spherical ; manubrium destitute of oral tentacles 5 radiating 

 canals six ; marginal tentacles six, springing from non-ocellated 

 bulbs. 



Lar sabellarum, Gosse. 



Polypites about -^ inch in height ; a patch of thread-cells 

 near the summit of the terminal lobe ; mouth furnished with 

 two broad lips ; tentacula very extensile, smooth. 



Gonozooids Isorne in clusters of three or four on the upper 

 portion of the slender blastostyles : umbrella (at the time of 

 liberation) colourless, destitute of thread-cells ; manubrium 

 subcylindrical, slightly swollen at the base, of a reddish-brown 



* Cases like the present, in which two family names are identical while 

 the names of the typical genera differ {Lar, Lams), are likely seldom to 

 occur. 



