﻿478 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 102 



TERMINOLOGY OF THE PARTS OF THE INTERNAL MALE 



GENITALIA 



The terminology used in this paper is based on that proposed by- 

 Alex. D. Baker in "A Study of the Male Genitalia of Canadian Species 

 of Pentatomidae," Can. Journ. Res. vol. 4, pp. 148-220, 1931. Unfor- 

 tunately the homology of the vesiculae situated at the apex of the 

 aedeagus in Mecidea remains obscure. Structures referred to by 

 Baker as titillators are either absent or are represented by the structure 

 treated in the present paper as the median vesicula. This is an 

 impaired, distensible structure located above the basal attachment of 

 the penisfilum. The structures treated by Baker as the median lobes 

 may be the same as are here termed penial plates. In Mecidea these 

 penial plates are paired, sclerotized structures which are connected to 

 each other basally and are attached on their ventral face to the dis- 

 tensible lateral vesiculae. The latter structures are undoubtedly the 

 same as those that Baker called the lateral penis lobes. 



The key is unsatisfactory in several respects. The degree of 

 variation shown by the various structures which, of necessity, are used 

 for construction of the key is such that many species must be keyed 

 out in two or more places. In addition, the absence of, or insufficient 

 number of specimens representing several Old World species makes it 

 impossible satisfactorily to key out more than 4 of the 14 species 

 involved. 



KEY TO THE SPECIES OF MECIDEA 



1. New World 2 



Old World 11 



2. (1) With dark markings on midventral line of abdomen. 



minor Ruckes (p. 490) 

 Without dark markings on midventral line of abdomen 3 



3. (2) Males 4 



Females 8 



4. (3) With a tubercule near the posterior ventral margin of the hypopygium 



(see pi. 48, fig. 53) minor Ruckes (p. 490) 



Without such a tubercule (see pi. 48, fig. 52) 6 



6. (4) Third segment of antenna shorter than second segment. 



major, new species (p. 486) 



Third segment of antenna equal to or exceeding length of second 



segment 6 



6. (5) Black spots just below abdominal setigerous punctures each with greatest 



diameter equal to one-eighth length of its supporting segment. 



major, new species (p. 486) 



Black spots just below abdominal setigerous punctures each with greatest 



diameter equal to no more than one-twelfth of its supporting 



segment 7 



7. (6) Pronotum strongly constricted just in front of the humeral angles. 



longula Stai (p. 484) 



Pronotum with lateral margin regularly and shallowly concave from 



humeral angle to anterior angle pampeana, new species (p. 495) 



