NO. 3 HEMOLYMPH COAGULATION IN INSECTS 21 



185 species not yet investigated, has been observed on films in vitro 

 by phase-contrast microscopy. In that material, the pattern of coagu- 

 lation predominant in the samples or representative for the species 

 or for the supraspecific taxonomic category has been recorded. 



2. The material contained insects from 14 families poorly (Dictyo- 

 pharidae, Cercopidae, Cicadellidae, Flatidae) or not (Gelastocoridae, 

 Membracidae, Cixiidae, Issidae, Cebrionidae, Lymexylidae, Erotyli- 

 dae, Hispidae, Corydalidae and Larvaevoridae) represented in pre- 

 vious studies. 



3. Additional information obtained for the present paper was con- 

 sistent with former data, with regard to the pattern predominant or 

 representative, in the Orthopteroid Complex, in several families of 

 Heteroptera (Reduviidae, Pyrrhocoridae, Coreidae, Pentatomidae, 

 Miridae), of Homoptera (Cicadidae, Fulgoridae, Dictyopharidae, 

 Cercopidae, Cicadellidae), of Coleoptera (Scarabaeidae, Elateridae, 

 Tenebrionidae, Meloidae, Cerambycidae, Curculionidae), of Hymen- 

 optera (Formicidae, Vespidae, Sphecidae). 



4. In the families not represented in former investigations, pat- 

 tern I was recorded in specimens of Cebrionidae and of Lymexylidae 

 ( Coleoptera) . 



5. Pattern I was also observed in specimens of Corydalidae (Sialo- 

 dea) and of Hydropsychidae (Trichoptera), in agreement with pre- 

 vious results on palearctic representatives belonging to these groups. 



6. Divergences in the reactions of coagulation observed in the 

 present and in a former study between Neotropical and African 

 Passalidae and Copridae (Coleoptera) require further investigations 

 on more extensive material, owing to the large variations existing in 

 these groups of insects. 



7. The reactions of the blood in vitro observed in five specimens of 

 Arachnida (Araneae, Ixodidae, Opiliones, Pedipalpa) are briefly men- 

 tioned in relation to previous results on more extensive material. 



ACKNOWLEDGMENTS 



I am grateful to Dr. Carl B. Koford, former resident naturalist of 

 the Canal Zone Biological Area, for invaluable help in supplying me 

 rapidly with adequate equipment. I also wish to express my thanks 

 to Mrs. A. Gomez, administrative assistant at the station, who, as 

 usual, was very cooperative in arranging for living accommodations 

 in the Canal Zone. 



I am greatly indebted to Dr. Ing° Oswaldo Vargas Gonzales, 

 head of the Seccion Entomologia de la Estacion Experimental Agri- 

 cola en Tingo Maria (Peru), for authorization to carry on my work 



