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families: Notodelphyidce (proper) and Doropygidce, and 2 other very distinct 

 families, BotryllophilLdce and Enterocolidce, are here added. The present 

 division thus comprises at least 6 families, and I regard it as very probable* 

 that their number will still be augmented, on a closer investigation of the 

 many peculiar forms found by Hesse within compound Accidians, but rather 

 imperfectly described by that author. 



Fam. 1. Notodelphyidae. 



General Characters. Body in both sexes cyclopoid in shape and more 

 or less straight, with the anterior division somewhat depressed, the posterior 

 much narrower and cylindric in form. Exposed part of trunk composed in male of 

 the usual number of segments, whereas in female the last 2 segments are confluent, 

 forming together a large median piece somewhat broader in front than behind 

 in young specimens, but in the adult female greatly expanded behind, to form 

 dorsally a very voluminous, somewhat flattened bag or incubatory pouch, into 

 which the ripe ova are received. Tail composed in both sexes of 5 segments 

 not very different in size. Caudal rami well developed and provided at the 

 end with strong ciliated setae present in the usual number. Eye of the structure 

 generally met with in the Copepoda. Anterior antennae of moderate size, and 

 extended laterally, being composed of numerous short joints densely clothed 

 with setae; those in male distinctly hinged. Posterior antennae much smaller 

 than the anterior, but distinctly prehensile, each terminating in a strong mobile 

 claw. Oral parts, as a rule, well developed, and built on a somewhat similar 

 type to that in the family Cyclopinidce. The 4 anterior pairs of legs likewise 

 cyclopoid in structure, and adapted for swimming; 5th pair of legs extremely 

 small and rudimentary, biarticulate. 



Remarks. This family is here taken in a much more restricted sense 

 than done by Thorell, who included into it also his 2 genera Doropygus and 

 Botachus. In the restriction here adopted, the family only comprises 2 genera, 

 viz., Notodelphys Allman and Agnathaner Canu. 



