BIBLIOGRAPDY OF PALAOZOIC CRUSTACEA 
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RAYMOND (Percy E)—Continued 
ginatus Billings (syn. B. minganensis Bill.), B. glandicephalus Whitt., B. angelini 
Billings, B. acutus sp. nov., B. arcuatus Bill., B. spiniger Hall, B. ingalli sp. nov. and 
B. schucherti Clarke. 
With Bathyurus mero Bill., for a type the author proposes the new genus Petigurus. 
The genus is closely allied to Bathyurus, but differs as follows: 
The facial suture reaches the posterior margin near the genal angle, the anterior 
end of the glabella overhangs the concave border; glabellar furrows are entirely ab- 
sent, and the eyes are somewhat farther forward. ‘The pygidium is without concave 
border, the ribs of the pleural lobes are reduced to nodes, and the axial lobe is ringed 
for almost its entire length. 
Petigurus Nero (Billings) an Irish species described by Reed, 1910, as Bathyurus aff. 
nero, differs in the posterior end of the facial suture, turns sharply outward behind the 
eye, forming a broad, fixed cheek, different from Pefigurus nero, and from any species 
of Bathyurus. 
The author also refers to the genus Petigurus cybele (Billings). 
Family Solenopleuridae Angelin: 
The author gives the following diagnosis of his new genus Hystricurus: Type Bathy- 
rus conicus Billings. 
Glabella conical, tapering towards the front, outlined by deep furrows at sides and 
front; glabella furrows absent; fixed cheeks long, extending nearly to the genal 
angle; dorsal furrows paralleled by a narrow, convex ridge; eyes of medium size, situ- 
ated opposite the middle of the glabella; cranidium with deeply concave border in 
front; pygidium rounded, with concave border, axial lobe prominent, with 5 rings, 
and there are 5 pair of ribs on the pleural lobe; surface smooth or pustulose. 
In addition to the type which the author illustrates, he includes under the genus 
Hystricurus crotalifrons (Dwight, 1884) and HH. cordai (Billings), B. seelyi Whitf. 
Bull. Am. Mus., vol. 2, p. 62, pl. 13, figs. 8-14, as a synonym, and not B. seelyi, vol. 1, 
1886, referred to Bolbocephalus. 
Family Proetidae Barrande: 
Genus Haploconus nov. This genus is proposed to include Vrilobites related to 
Cyphaspis, but differing in not having isolated basal lobes on the glabella, and in 
having a less prominent axial lobe on the pygidium. Type Bathyrurus smithi Billings. 
The author describes HI. smithi, and includes in the genus Cyphaspis 2? galenensis 
Clarke, and probably C. ? brevimarginata Walcott. 
Family Dikelocephalidae, Miller, 1889: 
Miller includes in the family Dicellocephalus, Pterocephala and Ptychaspis. 
The author proposes the new genus Platycolpus, for Bathyurus capax Billings, a 
Trilobite with hemispheric, rather smooth cephalon, a depressed glabella extending 
to the anterior border, which is a flat, striated rim; glabella furrows faint or absent; 
eyes small, situated midway on the length of the head; facial sutures cutting the pos- 
terior margin just inside the genal angles, and the anterior margin in front of the eye. 
Pygidium semi-circular, without depressed border and with faint traces of segmen- 
tation. 
The author describes Platycolpus capax (Billings), P. eatont Whitf., which has faint 
glabella furrows, also P. dubius with a more pointed glabella, and P. barabuensis Whitf. 
with a more convex glabella. 
Family Agraulidae Dalman: 
Under the new genus Plethopeltis with 4 graulos saratogensis Walcott, for the type 
the author gives the following diagnosis: 
Cephalon strongly convex, wider than long, without concave border or marginal 
tim; glabella faintly defined, without glabella furrows; eyes small, situated well for- 
