36 



SCIENCE. 



[N. S. Vol. XXIII. No. 575. 



Opposed to this theory are the following facts : 



(1) The natural mounds in many cases do not 

 occur in situations favorable for camp sites. 



(2) They often occur in elevated locations, 

 where there is absolutely no reason for arti- 

 ficial ' elevated sites for habitations.' (3) 

 Regarded as ruined habitations, or wigwam 

 sites, it is very important to consider their 

 vast number and the extent of territory cov- 

 ered. On this basis they would indicate, in 

 many parts of Louisiana and Texas, an in- 

 tensity and multiplicity of life not now dupli- 

 cated in any rural community in the world. 

 The sustenance of such vast commuriities 

 would be entirely beyond the capabilities of 

 the people who built the true Indian mounds. 

 (4) The natural mounds generally occur on 

 the poorest land in the northern Louisiana 

 region, and this fact is strongly opposed to 

 any supposed agricultural significance. 



No one doubts that there are numerous 

 Indian mounds throughout this region, but 

 the natural mounds belong to an entirely dif- 

 ferent class and should not be confused in 

 this discussion with the artificial ones. 



A. 0. Veatoh. 

 U. S. Geological Subvet, 

 Washington, D. C, 

 December 2, 1905. 



SPECIAL ARTICLES. 



THE TERMINOLOGY OF ABERRANT CHROMOSOMES 



AND THEIR BEHAVIOR IN CERTAIN HEMIPTERA.' 



Comparative studies of the last few years 

 have brought to light the occurrence of dif- 

 ferent kinds of chromosomes within the same 

 cell, curiously modified or aberrant structures. 

 These have been described in the spermato- 

 genesis of various insects, as in the Orthop- 

 tera (by McClung, Wilcox, de Sinety, Sutton, 

 Baumgartner, Montgomery, Stevens), the 

 Hemiptera (by Henking, Montgomery, Paul- 

 mier, Gross, Wilson), Odonota (McGill), and 

 Coleoptera (Voinov, Stevens) ; in Chilopoda 

 (by Blackman and Medes) ; and in Aranese 

 (by Wallace and Montgomery). I have shown 

 that they are not present in the Protracheata 

 {Peripatus). For these a considerable variety 

 of names has been proposed, most of which 



' Publications from the Zoological Laboratory 

 of the University of Texas, No. 71. . ■' 



are good appellatives, but all are inconvenient 

 on account of their length or double form. 

 There is a pressing need for a conciser and 

 more uniform nomenclature, and the follow- 

 ing terminology is here proposed to cover the 

 three known kinds of chromosomes found to 

 occur in the groups above mentioned. 



Chromosome, a name introduced by Wald- 

 eyer, to be retained on account of its long 

 usage as a convenient collective term, and 

 also to be applied in those cases where all the 

 chromosomes of a cell show essentially the 

 same behavior. But when more than one 

 kind occurs in a cell, they are to be distin- 

 guished as follows: 



1. Autosoma (or autosome), the usual or 

 non-aberrant chromosomes, called by me pre- 

 viously ordinary chromosomes. 



2. AUosoma (or allosome), the modified 

 chromosomes that behave differently from the 

 preceding. This term is much more con- 

 venient than the appellative heierochromo- 

 some previously proposed and used by me, 

 for the latter has an excessive length. Two 

 kinds of allosomes are known in spermato- 

 genesis and may be named respectively: 



(a) Monosoma (or monosome), allosomes 

 that are unpaired in the spermatogonia. 

 These have been variously termed accessory 

 chromosomes (McClung), chromosomes spe- 

 ciaux (de Sinety), chromosomes x and un- 

 paired ordinary chromosomes (Montgomery), 

 and heterotropic chromosomes (Wilson). 



(h) Diplosoma (or diplosome), allosomes 

 that are paired in the spermatogonia. These 

 correspond to what have been previously de- 

 nominated chromatin nucleoli (Montgomery), 

 Chromosome nucleoli (in parte), small chro- 

 mosomes (Paulmier), and idiochromosomes 

 (Wilson). 



It is after considerable hesitation that I 

 decided to propose these new names, for cell- 

 ular nomenclature is already heavily over- 

 burdened, and I do so in the hope that they 

 may be accepted in the spirit in which they 

 are ofiered, namely, to attain greater brevity 

 and convenience in writing. ■ When one has 

 to use words frequently he desires them as 

 short as possible. And though I call upon 

 fellow workers to discard their previous names. 



