User blog comment:Soulreaper1234/Is Vasto Lorde the 10 Espada or just another Hollow Being of higher capabilities?/@comment-1961713-20100608014756

Lets start with (refer ch284)

1.Gillian they are the lowest menos are hollows who desire other hollow souls, congregate together by feating on each other, meld together, lose their individuality and they become ridiculously huge beings that posses enormous amount of spirit power

2. Adjuchas - rare occurrences in Gillians where upon transformation an individuality that has not completely lost, surfaces, they continue to consume other Gillians and thus change into this. Adjuchas for fear of falling back into Gillians level they will continue to eat other adjuchas in order to maintain the Adjuchas form

3. Vasto Lorde - from Grimmjow memory - Shawlong Kufang pleads him to eat all the other that they have accepted they will not become Vasto Lorde because it is they fates, while Grimmjow because of his strength they are sure he will become one after eating all of them

Really my own opinion was that 10 Espada was indeed Vasto Lorde because they resemble human form. But because they were not explain in details the Espada's identity - the majority of the fans - cannot accept that all the known Espada were Vasto Lorde because they believe the Hollow evolution includes 1. Gillian, 2. Adjuchas, 3. Espada 4. Vasto Lorde. The most confusing part here was 3 and 4. But I do believe when the Ichigo-Grimmjow battle concluded Kubo did explain briefly how Grimmjow had become King or a Vasto Lorde as Shawlong Kufang pointed out.