222 MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES, 



discul venules either situated nearer the base of the wings than usual, either forming a quite regular 

 curvilinear line (subrotata and f/uttivitta), or the hinder venule is decidedly bent inward {hydromeli 

 and unicolor) or regularly curved inward (biundata). 



Legs rather stout, with thick, long tufts of scales; fore tibiffi with flat spreading tuft; hind 

 tibia^ with two pairs of large, nearly equal, long, sharp spurs. Abdomen long, cylindrical, not 

 tufted at the end, nor densely woolly, as in Certira. 



Coloration: The species are quite variable, but more or less dull gray, with indistinct scalloped 

 transverse lines and an obscure linear or a twin discal spot ; hind wings gray, with a faint interrupted 

 diffuse outer line, or whitish; in the mibrotaia group the fore wings are pale ash, with tawuy 

 blotches at the base, and diffused over the wing, while the dark markings are more distinct. 



The genus is characterized by the unusually short hind wings, with their well-rounded apex; 

 the front of the head is rather narrow, the palpi stout and usually broad; the thorax very hairy 

 beneath. The species are nearer those of Schizura than any other genus of the family, showing 

 no near relationship to Cerura in adult characters, except the width of the head on the vertex. 

 The limits of the genus are doul)tful, and some authors may in the future decide to divide it into 

 several, perhajts retaining Lochnueus and Cecrita as genera. I have been inclined to do this both 

 from the venation and the larval characters, but when we take into consideration the unusual 

 amount of individual variation in the venation such a course seems hazardous. If any division 

 were to be made it nnist be to retain LochnurHS for a single species, manieo. 



The genus may be divided into five subgenera, which are, however, more or less artificial, and 

 appear to be perhaps incipient subgenera the result of the specialization of the type in different 

 directions. 



Subgenus 1. Fore winga long, apex squarish; hind wings well rounded; in the hind wings the second 

 subcostal venule arising halfway between the subcostal and independent H, (Lochma-us) manteo 



Subgenus 2. Fore wings rather long, apex pointed; liin<l wings rounded, short; palpi not very thick and 

 stout; fore wings gray, with olive-green or reddish tints, and obscure scalloped inner and outer lines; 

 discal mark diffuse and indistinct; discal venules in both wings forming a regularly curved line. 



H, (Cecrita) umhrata. ohliqiia, astarte, guttivUiu, hiiinilata, and phimosa 



Subgenus 3. Antenna; with longer pectinations th;m in the other species: fore wings short, broad and siiuare 

 at the apex (subrotata and liiitlromcli) ; venation variable, the discal venules together forming an oblique 

 curve. .suhrotata 



Subgenus 4. Discal venules forming a rather sharp angle directed inward, and situated between the inde- 

 pendent venule and the first cubital venule. Female autenmo nearly as well pectinated as in the male. 



H. (LUodonta) hijdromeli 



Subgenus 5. Fore wings moderately long, with the outer edge bent, the fore wings very uniform in color, 

 and without distinct markings of any kind ; venation nearly identical with that of astarte and obliqita. 



H. unicolor 



The generic characters of LUodonta given by Harvey were these: "It differs by the antennae 

 being pectinate in both sexes. 'The thorax is more brushily tufted behind ; the head more appressed ; 

 the abdomen shorter." It seems to us that these characters are not of generic value, as //. subrotata 

 is very near H. hydromeli, but others may prefer to retain the genus as distinct, at least until 

 something is known of the larval history. 



Larva. — Body usually thickened in the middle; head with a red lateral band edged with white 

 or with white and yellow, with equal red lines, the space between clear green, or filled in on first, 

 third, and sixth abdominal segments with red, which in some species extends down on the side; 

 aual legs either normal or long and slender. In Stage I larva either normal, unarmed, or with 

 from one to nine pairs of deer-like antlers; anal legs with normal or (E. unicolor) with long, 

 slender, eversible ends. 



Cocoon. — Regular oval, translucent, like very thin parchment iu color and structure: spun 

 between leaves. 



Piy;«._Body usually thick and plump; front of head with two parallel, slightly marked ridges 

 between the eyes; cremaster armed with two stout, large, conical spines, differing much in shape 

 in the different sjtecies. 



Geographical distribution.— The genus is confined to the New World and the species range from 

 Nova Scotia and Maine to Mexico, Central America, Surinam, and Brazil. At present more species 



