User blog comment:Kartik "k2"/Comparision between regular shinigami/Hollow and Vizards/Arrancars/@comment-24165551-20140918174003/@comment-493809-20140918223508

Ulquiorra's Hollow form was shown in a bonus chapter and I'm 90% sure he was Vasto Lorde. As you said though, Nnoitra and down were most likely Adjuchas (barring Jarhead, the sole Gillian of the group).

Again, Harribel was defeated by Hitsugaya pre-Ressurecion - she then broke out of the ice and did fine until Aizen decided she had outlived her purpose.