Feb., 1905.] Nerthra stygica. 287 



NERTHRA STYGICA SAY AND SOME NOTES ON THE 

 FAMILY GELASTOCORID^. 



J. R. DE LA Torre Bueno. 



In 1832* in his ' 'Descriptions of Neiv Species of Hemiptera, 

 Heteroptera of North America,'' Thomas Say described his 

 "Naucoris stygica" from one mutilated specimen from Georgia. 

 Its structure led him to propose a new genus for it, to be called 

 Nerthra. From that time to the present the real "Nerthra 

 stygica" has been lost to science. It is true that Monon3'x 

 stygicus Say is mentioned by Uhler as well as by Comstock in 

 some of their works, but from the description of it given by the 

 first-named author in Kingsley's ''Standard Natural History" it 

 is evident that the references are not to Say's bug, but either to 

 Mononyx fuscipes Guerin or to M. nepasformis Fabricius. It is 

 one of these two that Dr. Howard figures in his ''Insect Book." 

 In support of this view is the fact that all the American works 

 and papers which have been consulted fail to mention the most 

 striking peculiarity of Nerthra; namely, the hemelytra soldered 

 together and extremely roughened. The genus and species are 

 cited in Stal's ''Enumeratio Hemipterorum," while on the other 

 hand, Montandon, in his revision of the subfamily ' 'Monychinae" 

 doubts its very existence, for he says that to his knowledge it has 

 not again been found in America and, quoting Say's description 

 in extenso, remarks it ' 'would lead one to believe that he (Say) 

 had before him a form near to or identical with Matinus or 

 Peltopterus and in any case differing from Mononyx." 



In the absence of Guerin's original generic characterization of 

 Peltopterus, it has been referred to the description of the latter 

 genus in Stal's ' 'Hemiptera Africana" (Vol. Ill, p. 173), to which 

 genus Nerthra is nearest, on account of the entirely coriaceous 

 character of the hemelytra. It differs, however, in the shape of 

 the body, the apical tubercles of the head and the shape of the 

 thorax and hemelytra. (This last may be a merely specific 

 character.) It becomes, therefore, evident that Say's genus 

 Nerthra stands, and since the very existence of the bug is ques- 

 tioned by no less an authority than the Rumanian Hemipterist 

 and so much misapprehension regarding it seems current I ven- 

 ture to attempt a description from the onlv specimen I have seen, 

 giving the bibliography and synonymy as far as known to me. 



Nerthra Say, 



1831 (1832 sec. Uhler)— Description of N. Sp. of Het. Hem. of N. A., p. 808. 

 1859— Compl. Writ, of T. Say, ed. by Le Conte, Vol. I, p. 364. 

 1876— Stal, Enum. Hem., V., p. 139. 



* Prof. Uhler in a letter to Mr. G. W. Kirkaldy expresses the opinion that although 

 Jbhis paper is dated 1831,|it'did not appear until March, 1832. 



