v HISTORY OP ACHATINELLID^. 



Alexander, better known for his work in other directions, 

 also contributed to Mr. Gulick 's material. 



John T. Gulick began collecting Achatinellida in 1850, at 

 the age of 18. Most of his collecting was done between that 

 time and 1853. His work differed from that preceding by 

 the careful attention given to locality and food-plants of the 

 snails. He was also the first to collect the small ground- 

 shells, especially Leptachatina, extensively, as he was the first 

 to appreciate their characters. Two descriptive papers were 

 based upon this most comprehensive and valuable of all the 

 early collections. The first was published in 1856 ; the second, 

 in collaboration with Mr. E. A. Smith, not until 1873, though 

 dealing with material collected in the early fifties. 



Mr. Gulick 's descriptive work, like his field work, was on 

 a higher plane than that of his contemporaries. He sought 

 to record the marvelous variation and differentiation of the 

 island fauna. The suggestive geographic relations of allied 

 forms made strong appeal to his imagination. One sees the 

 same trend of thought in C. B. Adams' Jamaican papers of 

 about the same date; and as everyone knows, Darwin had 

 been deeply impressed by similar phenomena observed in the 

 Galapagos. 



Many of the species of Gulick are now given another inter- 

 pretation or value ; many have been confirmed by subsequent 

 investigations. His classification of the group (P. Z. S. 1873) 

 was a long stride forward, improving the arrangements of 

 Pfeiffer and von Martens in important details. Though this 

 work is concerned chiefly with systematics, allusion should 

 be made to Gulick 's greatest intellectual service, his theory 

 of segregation in its several forms, as a necessary condition 

 of the evolution of species, originally suggested by his studies 

 on Oahuan Achatinellidae. First stated in 1872, it was fully 

 discussed in his "Evolution, Racial and Habitudinal, Wash- 

 ington, 1905. 



W. H. Pease, whose occupation as a surveyor took him 

 over Kauai and other islands, published several new species, 

 and in 1869 a classification and catalogue of Achatinellida. 



From 1855 on there seems to have been little scientific col- 



