21 
MEMOIES OF THE iN^ATIONAL ACADEMY OF SCIEi^CES. 
The following table is au attempt at a classidcation of some of the structures arising from 
the various modifications of the primitive piliferous warts or tubercles common to nearly all, if not 
all, smooth-bodied lepidopterous larvie. As is well known, the term hair’’ does not properly 
apply to the bristles or hair-like structures of worms and Arthropoda, as morphologically they 
are not the hoinologues of the hairs of mammals, but arise, as Kewport first sliowed, through a 
moditication and hypertrophy of the nuclei of certain cells of the cuticle. Hence the word seta, 
as suggested by Lankester, is most ap[)licable, 
A.— Tujbkrcles. 
a. Simple aud minute, due to a slight thickening of the hypodermis and a decided thickening of the over- 
lying cuticle; the hypodermis contains a large unicellular glaiul, either for the secretion of the seta or for the 
production of poison. 
1. ^Minute piliferous warts. (Most Tineid, Tortricid, and Xoctuid larvffi.) 
2. Enlarged smooth tuhercles, hearing a single seta, (Many Georaetrid and Bomhyciiie larvje.) 
3. Enlarged spherical tubercles, bearing a number of setie, either radiated or subverticillate. (Arotians, Lithosiaiis^ 
Zygjcnidip, including some Glaucopina*.) 
4. High, nioval)le, smooth tuhercles, having a terrifying function. (Schisura, Xylinodes, Xotodoiita, Xerice.) 
5. Low and broad, rudimentary, replacing the “caudal horu.’^ (ClKcrocampa, the European Pheosia cJictwa, and 
diclwoides.) 
h. More or lees epmuloee or spiny (disappearing in some Sphinges after Stage I). 
1. Long ami slender, usually situated on top of the eighth abcloininal segment, wdth microscopic spinules in Stage I. 
(Most Sphiuguhe and Sesia.) 
2. Smooth 8ubs[jherical warts. (Zygn?mdip, e. g., Ghalcosia, East Indies) ; or elongated, hut still smooth. (Attacus 
atlas, and a species from Southwestern Territories, IT. S. A.) 
3. Subspherical or clavato spiny tubercles of many Attaci; the spinules usually short. 
4. Spinulated spines or elongated tubercles of Ceratocamipda* and llcmilucidip. (/I. io and JJ. maia, etc.l 
5. Spike-like hairs or spines, (.Sarnia cynthia, Auisota, East Indian llypsa, Anagnia.) 
6. Antler-like spines. Early stages of Heierocampa biiindata, gntlivitta and obUqua.) 
B. — Skt.e (“Haius,” Bristles, etc.). 
1. Simple, line, short or long, microscopic or macroscopic setie, tapering hairs, scattered or dense, often forming- 
pencils. (Many Bombyces, Zygieuidic, Noctuo-boinbyces, Apatelm ) 
2. Glandular hairs, truncate, .spindle-shaped or forked at the end, and secreting a more or less viscid fluid. (Many 
in Stages I and II of Notodontians, many butterfly larvm, and in the last stages of Pterophoridic.) 
3. Long, spindle-shaped hairs of Apatelodes, Apatcla americana, figured in Harris Corr., PI. Ill, flg.2; also Packard's 
Guide, tig. 230, and the European Tinolius ehnrneUjuUa Walk. 
4. Ehittened, triangular liairs in the tufts or on the sides of the body of GastropacJia americana, or flattened, spindle- 
shaped scales in the European G. quercifolia.* 
5. Siiiniihitcd or barbed hairs. (Most Glaucopides, etc., Arctians, Lithosiaus, and Liparidiu, and many other 
Bombyces.) 
C. — Pseudo-tubercles. 
1, The filameutal anal legs (stemapoda) of Cerura and Heterocampa marthesia. 
2. The long suranal spine of Platyptericuhe. 
THE USUAL POSITION OF THE MORE SPECIALIZED WARTS, HUMPS, OR HORNS. 
Every^Jody lias noticed that the horn characteristic of larval Sesim and Sphinges is uniformly 
situated on the back of tlie eighth abdominal segment and uo other, and that when it is absent, 
as in Clujerocampa, etc., it is replaced by a small, low, and flattened tubercle, the segment itself 
being somewhat swollen. The larval Agaristidie (Alypia, Eudryas, Copi<lryus, Ps^'chomorpha, 
etc.) have a pi’omiiient, gibbous hump on this segment, or at least this segment is more or less 
prominent and humped, not only in this family, but also in certain smooth-bodied E'octuidm, as 
Amphipyra, and Olygia versicolor, etc. 
In many Xotodontidm the first abdominal segment beai’s a conspicuous hump, sometimes 
forked, often ending in a seta. 
Ill the larval OeratocampidiU, either the prothoracic segment or the second and tliird thoracic 
segments bear high conspicuous horns and spines. They may be roughly classified as follows: 
^See my article in Annals and Magazine of Natural History. Ser. 6. ix. pp. 372-375. 1892. 
