No. 5 — The Genus Tetragnatha (Araneae, Argiopidae) in Panama By Arthur M. Checkering Albion College, Albion, Michigan As a result of several visits to the Canal Zone and the Republic of Panama for the purpose of collecting and studying spiders I have accumulated a rather large number of specimens belonging to the interesting genus Tetragnatha Latreille, 1804. The present study of the genus is specifically concerned with its occurrence in Panama where it appears to have found exceptionally favor-able conditions. Araneologists who have interested themselves in the genus Tetragnatha have emphasized such characters as the following: size of the body ; shape of the abdomen ; relative position of the eyes ; several features of the chelicerae and cheliceral teeth ; color ; relative lengths of the different segments of the male palp ; specific characteristics of the male palpal tarsus; presence or absence of spines on legs and their length. F. P. Cambridge (1903) paid close attention to the characters and relationships of the con-ductor and embolus in male palps. Petrunkevitch (1930) also did this and, in addition, gave careful attention to the appear-ance of the genital fold in females which are often difficult to place with certainty because of the absence of an epigynum and other marked characteristics. My experience with the genus seems to show that close attention must ahvays be given to the specific shape of the conductor and embolus as well as to their relationships. These features appear to be the least variable among all of those used by taxonomists and, therefore, the most reliable for purposes of accurate determination. In females the characters of the genital fold are often very helpful. Size ; color ; number, relative size, and placement of the cheliceral teeth are all subject to a rather wide range of variation. These facts seem to explain the numerous errors in identification which can be found in almost every collection. In making. this study I have tried to take into consideration all of these items in making my identifications and in drawing conclusions regarding synonymy. Acknowledgments arc again <lue and p'ratefullv extended to the
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