744 



SCIENCE 



[N. S. Vol. XXV. No. 645 



flattened area on the face, but without groove 

 or channel. Zapupe azul, in habit, form of 

 leaf and spines seems to agree perfectly with 

 Tequila azul, Agave tequilana Web., culti- 

 vated extensively in the region of Tequila, 

 Jalisco, for the production of ' Tequila wine.' 

 The plant is not used for the production of 

 liquor in eastern Mexico. It is said to have 

 been introduced in that region and its origin 

 seems uncertain. Zapupe verde has long been 

 cultivated for fiber by the Indians of Tauto- 

 yuca. Vera Cruz. The zapupe fiber morales 

 made by these Indians are among the finest to 

 be found in Mexico. This plant may be 

 Agave angustifolia Haw. which has been re- 

 ferred somewhat doubtfully as a synonym of 

 A. rigida. 



The fibers of both species of zapupe are very 

 similar in character. They belong to the sisal 

 group among the hard fibers used for twines 

 and cordage. They are finer, and more flex- 

 ible than either Yucatan or Bahama sisal, 

 approaching the better grades of Bahama sisal 

 in general character. In a test for tensile 

 strength they compare favorably with the bet- 

 ter grades of sisal. M. 0. Marsh, 



Recording Secretary 



DISCUSSION AND CORRESPONDENCE 

 THE FIRST SPECIES RULE 



I HAVE read with a great deal of interest 

 all that has been more recently published in 

 Science on this topic, because the adoption of 

 and strict adherence to the rule making the 

 ' first species ' the generic type will make 

 about as many changes in the nomenclature 

 of the lepidopterous family in which I am 

 especially interested as can well be crowded 

 into it. It will bring up names that have 

 dropped out of use for fifty years and it will 

 completely change the conceptions of a large 

 number of genera that have been in common 

 use for nearly or quite as long a period. 



I was particularly interested in the essay by 

 J. A. Allen in the April 5 number of Science 

 and especially in the following, on p. 548: 



Of course, an author often states that certain 

 species are referred to a given genus provisionally, 

 or are given as doubtfully belonging to it. In all 

 such cases the. rules of our standard codes prohibit 



the taking of any such doubtfully referred species 

 as the type of a genus. 



Ordinarily when an author characterizes a 

 genus he has some definite idea that represents 

 his genus — a combination of structures which, 

 taken together, make his generic conception. 

 Whenever there is any change in this associa- 

 tion by extension or limitation the genus as 

 first proposed is no longer in existence. As 

 limited or enlarged the association of species 

 represents the conception of the person that 

 limits or extends. 



In 1890, in a revision of the species listed 

 under Agrotis in our catalogues, I proposed 

 the name Ehynchagroiis for an assemblage 

 most prominently characterized by a palpal 

 structure that bore a resemblance to a short 

 snout or beak. Thene were other characters as 

 well and the combination of those characters 

 made up my genus for which no type was 

 designated. 



Among the species referred to this new as- 

 sociation was Agrotis chardynii (gilvipennis 

 Grt.), an oddity in our fauna, standing by 

 itself and differing markedly from all our 

 other forms. It did not really agree with 

 my definition of Rhynchagrotis and so I 

 stated; my reason for placing it there being 

 that I believed it would prove to be properly 

 referable to an exotic genus to which I did not 

 care to risk making a synonym. 



In accordance with my usual practise in 

 revisional work I prepared a table of species, 

 and for convenience in tabular arrangement I 

 usually separate the oddities first. Thus, 

 chardynii being the only one of our species 

 with yellow secondaries was the first to be ex- 

 cluded in the synoptic arrangement, and the 

 list of species described under Rhynchagrotis 

 begins with that name. 



Eecently, Sir George Hampson, in his 

 monumental catalogue of the Phalsense in the 

 British Museum, treated the Agrotids in his 

 Volume IV., and as his basis for generic com- 

 binations did not coincide with mine, there 

 were some shifts. Among others my asso- 

 ciation under Rhynchagrotis was broken up, 

 and of all species in the world chardynii, which 

 I felt sure could not remain in it, has now 

 become the ' type,' because it happened to 



