102 Zoological Nomenclature. 
termed (through erroneous information os bn habitat) Picus cafer, or fone olive- 
colored one Muscicapa atra, or when a name is derived from an accidental 
monstrosity, as in Picus semirostris of Linnea, and Helix disfietla of Tur- 
ton, we feel justified in canceling these names, and adopting that synonym 
which stands next in point of date.* At the same time we think it right to 
remark that this abi pitts is Rise liable to zhane," nd ought therefore to be 
applied only to extreme c and with great caution. With these limita- 
tions we may concede that 
§ 11. A name may be changed when it implies a false pro- 
position which is likely to propagate important errors. 
[Names not clearly = sop be changed.|—Unless a species or group is 
pion ga! defined when the name is given, it cannot be recognized by 
and the signification of the bes is consequently 1 ee byt op pe 
are Gabon ary before a zodlogical term can acquire ority, viz., defi- 
pote and lication. Definition peoperty finplio a pons ar postion of 
ntial characters, and in all cases we conceive this to be pa 
tibet guar uthors maintain that a mere enumeration of the compone 
spec of asin ole type, is sufficient to wine pie a genus.t 
constitute ‘saisiulin, nothing short of the insertion of the above particulaté 
ed bok can be held a Many birds, ry in scokaities in the 
aris and other continental museums, shells in the British Museum (in Dr. 
Leach’s time) and _~ ils in the oa rborough and other pe collections, 
have receive ames, which will be of no pace ty u they are pub- 
lished = characters rhe r can any Supe lished deseriptions however ex- 
act (such as those of Fors which are still shut up in a MS. at Berlin), 
claim ve right of priority "tl pailiahed, aA then eae fecion the date of their 
publication. The same rule applies tocases where groups or species are pub- 
* Under this rule it would be well to exclude all names that refer to abnormal, 
diseased and mutilated structures, and wane caused by parasites. Thus 
roves to i i ; d ie 
us Val. pi 
but the gibbosity is caused only by a parasitic crab. lodged in the anal region, 
and is not present in normal specimens. Tenia mediocannellata was so suet 
m of establishing genera es merely ‘naming “ane or more species, 
without i initiontin any generic character o n giving figures, is exceedingly 
objectionable and liable to lead to prey ate "eopeuey ea” as often happens, 
he same author afterward describes the genus and adopts a different type 
Thus Toxopneustes Ag. was originally named with > beohdans pileolus” as 
its type; afterward it was described and E. tuberculatus Lam. (a specie 
generi cally distinct from the former) was named as ; 
later (in Catal. Rais.) the genus was extended s 
bereulatus and its ts allies, but also several other forms whic 
by uber 
type sidaris). Other serious difficulties arise when, as often happens, 42 
author’s type is bapa fa sing omc and pote not agree Ww with t the original species, 
g 5 spe e, even it 
t These MS. fades ne in ‘mn all cases liable . create cbatistct. and it is there- 
fore m much to be desired that the practice of using them should be avoided in 
Fert eee 
