Magazine  (28 Jul 1937)  Page(s) 56.  
 
TWENTY BEST LARGE-FLOWERED HYBRIDS OBTAINABLE IN THIS COUNTRY
Duchess of Albany* [see footnote] Texensis Type
All bloom on new wood except Belle of Woking and Sir Garnet Wolseley

*Or any other Texensis Hybrid, Duchess of York, Countess of Onslow, Grace Darling, Admiration, all with trumpet-shaped flowers in shades of pink or scarlet.

Website/Catalog  (1924)  Page(s) 106.  
 
Countess of Onslow (Hybride de coccinea). Violet pourpré, large band écarlate.

Website/Catalog  (1914)  Page(s) 109.  
 
Clematis Coccinea Hybrids
Countess of Onslow. Bright violet-purple, with a broad band of scarlet through the center of each petal.

Website/Catalog  (1912)  Page(s) 78.  
 
Hybrid Clematis.
The following are Hybrid varieties raised from C. Coccinea; they have been certificated by the Horticultural Society, and are decidedly pretty and most distinct.
Countess of Onslow, Bright violet purple, with a broad band of scarlet down the centre of each petal, it is of open bell-shaped form with four to six petals to each flower, it is very free and quite hardy...  1s. 6d.

Website/Catalog  (1907)  Page(s) 65.  
 
Clematis in pots to plant out in spring and summer.
New Varieties.
125 Countess of Onslow (coccinea hybrid), a bright violet purple, band of scarlet down each petal.

Magazine  (Sep 1906)  Page(s) 335.  
 
Tous les lecteurs du Lyon-Horticole ont certainement remarqué l'annonce placée en tète de ce journal, par laquelle la maison Ch. Molin invite tous les horticulteurs à venir visiter son jardin d'Exposition, nouvellement installé à Lyon-Montchat, 9, chemin des Sables..... Des Clématites grimpantes choisies parmi les variétés réfractaires à la maladie sont isolées de loin en loin au centre des plates-bandes. Leurs tiges sont supportées par une légère armature en fer de 2 mètres de haut. Les variétés fleuries au moment de notre visite sont : Comtesse Onslow, Duchesse d’Albany, nouvelle race hybride entre la Clem. Coccinea et les variétés à grandes fleurs, Ville de Lyon, Modesta, Perle d'azur, Viticella purpurea plena elegans, V. M^me Julia Correvon, Leonidas. V. alba, etc. 

Book  (1906)  Page(s) 54.  
 
Principal garden varieties of Clematis:
Viorna type.  (July to September.)
Coccinea hybrids.
Countess of Onslow... Violet-purple, scarlet band, bell-shape.

Book  (1904)  Page(s) 332.  
 
Climbing plants.
Flowers smaller, pitcher-shaped or tubular.
21.  Clematis Viorna, var. coccinea, A. Gray (C. coccinea, Engelm.). Leaves glaucous, subcoriaceous; leaflets broader than the type, often obtuse or retuse; sepals carmine or scarlet.  Texas.  Lav. 19 (as C. Texensis).  B.M. 6594.  Gn. 19:275.  Gt. 32:86.  R.H. 1878:10; 1888:348. — Much superior to the type, because of its beautiful flowers.  Some of the garden forms of this variety, which have probably been produced by crossing it with hardier Clematises, are found under the names: Countess of Onslow, deep scarlet, G. C. III. 16:9; Countess of York, white tinted with pink; Duchess of Albany, clear pink, Gn. 52:1140.

Website/Catalog  (1902)  Page(s) 11, 39.  
 
Clematis coccinea-Hybrids. "Countess of Onslow" and "Duchess of Albany".  Vigorous and healthy like coccinea are the jug-formed blooms of these hybrids, opening wide star-like at the front. 1 piece M. [Mark] 1.50, 10 pieces M. 12.50.

Website/Catalog  (1900)  Page(s) 17.  
 
NEW HARDY HYBRID CLEMATIS COCCINEA.
Countess of Onslow. Bright violet purple, with a broad band of scarlet through the center of each petal, of open, bell-shape form, with four to six petals to each flower, which are thick in substance and will be found useful for decorative purposes, and when cut will keep fresh in water for several days. Strong plants, $1.50 each.