^^ Includes: Opisthoparia, Hypoparia, Integricephalida, Oligomeria, Pliome- 

 ria, Protoparia, Epiparia, Polymera, Eodiscida, Olenellida. 



^® Delobranchia (Hydropneustea) = merostomata (sometimes + trilobito- 

 morpha). 



^'^ Includes: Synxiphosurida, Bunodomorpha, Limulida, Euxlphosura. 



^^ Includes: Colossendeomorpha, Nymphonomorpha, Ascorhynchomorpha, 

 Pycnogonomorpha. 



^^ Epectinata = all arachnida except scorpionida. Arachnoidea = class 



ARACHNIDA OF ARACHNIDA + MEROSTOMATA. 



