54 COCKERELL AND COLLINGE : CHECK-LIST OF SLUGS. 



71. bourgiijgnate =Jlav7is var. 

 A. briinuetis — onpiricorutn juv. 

 A. canipestris = empiricorum var. 



A. dnpiiyanus-=ftiscus var. 



A. fasciatHs= hortensis et fttsciis. 



A. intennedins = empiricorn7n juv. 



A. M?z'a//5 = valid species. 

 A. olivacetis = \a.\id species. 

 A. pascaliamis ^fuscits. 



and so forth. It is easy now to see how little the conclusions of the 

 authors of 1881 were to be trusted, but does this not suggest 

 possibilities concerning the opinions of authors of 1893? 



Finally, I will venture to make a suggestion regarding the list. 

 Let it be the basis of our classification until it can be improved ; and let 

 every slug-student send notes to the "Journal of Malacology"; which 

 may be published under the general heading of Additiot^s and 

 Amendments to the Slug List. Such notes, one might hope, would 

 be fairly numerous, especially just at first, as every student on reading 

 the list will be sure to think of several changes which seem to him 

 necessary or desirable. The proposed changes might be discussed 

 after publication by those who disagreed with them, and after a time, 

 it might be announced that a second (revised) list was about to 

 appear. Upon this announcement every student would write to the 

 Editor of the Journal, giving his latest opinions, and in due time 

 the list would a])pear, doubtless a vast improvement upon its prede- 

 cessor. As in the present list, some notes would be appended, 

 especially when it was necessary to explain the views of minorities 

 who disagreed with the classification given. In cases of great 

 difficulty, a post-card vote might be taken to decide a point. The 

 revised list would not of course, be in any sense final, but would be 

 followed by other editions as often as circumstances demanded or 

 permitted. 



If the funds could be obtained for printing, a new edition every 

 year would be very useful, and would give a great impetus to the 

 study. 



APPENDIX. 



By WALTER E. COLLINGE. 



Professor Cockerell has placed all students of the slugs under 

 a great obligation for so admirably and carefully compiled a check 

 list. Only those who have worked at this group, and have extended 

 their inquiries beyond the fauna of their own immediate country, 

 are fully able to appreciate the value of such a list as the present, 

 and whatever difference of opinion may prevail as to the validity of 



