Gray-crested Helmetshrike

Here the details of the Gray-crested Helmetshrike named bird below:

SCI Name:  Prionops poliolophus
Protonym:  Prionops poliolophus J.Orn. 32 p.180
Taxonomy:  Passeriformes / Vangidae / Prionops
Taxonomy Code:  gychel1
Type Locality:  Lake Naivasha, Kenya.
Author:  Fischer & Reichenow
Publish Year:  1884
IUCN Status:  Near Threatened

DEFINITIONS

PRIONOPS
(Vangidae; Ϯ White-crested Helmet-shrike P. plumatus) Gr. πριων priōn, πριονος prionos  saw; ωψ ōps, ωπος ōpos  eye; “BAGADAIS, Prionops.  Bec emplumé à la base, tendu, très-comprimé latéralement; mandibule supérieure échancrée et crochue vers le bout; l'inférieure retroussée et aiguë à la pointe. — Paupières dentelées.   Esp. Le Geoffroy, Le Vaill.   ...   Prionops [πριων, serra, ωψ, oculus].” (Vieillot 1816); "Prionops Vieillot, 1816, Analyse, p. 41. Type, by monotypy, "Le Geoffroy" of Levaillant = Lanius plumatus Shaw." (Rand in Peters 1960, IX, 310).  This genus was formerly and widely separated in the family Prionopidae, and some modern workers still favour that treatment.
Var. Trinops, Trionops (Laurent Raty in litt.).
Synon. Eressornis, Knestrometopon, Phaidrometopon, Sigmodus.

POLIOLOPHUS
(Pycnonotidae; Ϯ Yellow-wattled Bulbul P. urostictus) Gr. πολιος polios  grey; λοφος lophos  crest; "POLIOLOPHUS, gen. n.    76. POLIOLOPHUS UROSTICTUS. — Ixus? urostictus, Walden, t. c., p. 191, pl. xxxii. fig. 2.   ...   The combination of an eye-wattle and a crest seem to me to indicate that this bird should be placed in a distinct genus from Pycnonotus or Otocompsa; and I therefore propose the name of Poliolophus.  The colouring of the bird is very badly rendered in the plate accompanying Lord Walden's paper — the greyish crest not being defined, and the eye-wattle entirely omitted." (Sharpe 1877).
Var. Poliophilus.

poliolophus
Gr. πολιος polios grey; λοφος lophos crest.