154 MR. E. SHELFORD ON A NEW GENUS OF DIPTERA. 



ants almost disposes of the suggestion that these species have to be fed by 

 attendant hosts. Unfortunately, nothing is known of the habits of yEnig- 

 matistes ; the unique specimen was found in a miscellaneous collection of 

 insects sent to the Paris Museum by M. Ch. Alluaud. 



The following are the chai'acters in which ^nigmatistes resembles 

 y^nigmatias : — 



Cockroach-like appearance. 



Strongly chitinized head and tergites. 



Form of antennae. 



Form of maxillary palpi. 



Division of thorax into three visible segments. 



Abdomen beneath covered with an unsegmented membranous cuticle. 



Form of legs. 



Absence of tarsal pulvilli. 



The following are the characters wherein yEnigmatistes differs from 

 yEnigmatias : — 



Shape of the head. 



Position of the eyes. 



Absence of ocelli. 



Large size of the pronotum. 



Form of the mesonotum and metanotum. 



Four visible abdominal segments only. 



Bibliography. 



1. Meinert, F. — " yEnigmatias hlattoides. Dipteron novum apterum.''^ 



Entomol. Medd. vol. ii. pp. 213-226, pi. iv. (1890). 



2. Dahl, F. — " Pulicipliora, eine neue flohahnliche Fliegengattung."' 



Zool. Anz. 1897, pp. 409-412. 



3. Wandolleok, B. — " Die Stethopathidse, eine neue fliigel- und 



schwingerlose Familie der Diptera." Zool. Jahrb., Abth. Syst. 

 vol. ii. pp. 412-441, plates 25 & 26 (1898). 



4. Wasmann, E. — " Termitoxenia, ein neues fliigelloses, physogastres 



Dipterengenus aus Termitennestern." Zeitschr. wiss. Zool. vol. Ixvii. 

 pp. 599-617, pi. 33 (1900), and vol. Ixx. pp. 289-298 (1901). 



5. CoQUiLLETT, D. W. — " The occurrence of the Phorid genus yEnigmatias 



in America.'' Canad. Ent. vol. xxxv. pp. 20-22 (1903). 



6. Breddin& Borner, C. — "Ueber Thaumatoxena wasmanni, der Vertreter 



einer neuen Unterordnung der Rhynchoten." Sitz.-Ber. Ges. naturf. 

 Freunde, Berlin, 1904, pp. 84-93. 



7. Borner, C. — " Zur Systematik der Hexapoden.'' Zool. Anz. 1904^ 



pp. 511-533. 



