In every section of his description, Collado is indebted to the material presented by Rodriguez in his _Arte da Lingoa de Iapam_. The structure of the _Ars Grammaticae_, however, follows a much more simplistic design than that of the _Arte_. As a consequence Collado found it necessary to assemble his data from various sections of Rodriguez' description. In the paragraphs which follow we will briefly sketch the structural relation between these two grammars. As he clearly states in his title to the main portion of the grammar Collado bases his description on the _Introductiones_ of Antonio Lebriya, and more specifically upon that portion of the great Latin grammar which dealt with the parts of speech. Further, he limits himself to the spoken language rather than attempting, as does Rodriguez, an integrated treatment of both the spoken and written grammars. Under these influences Collado's grammar takes on the following form: A Prologue (including the phonology) 3-5 The Body of the Grammar (by parts of speech) 6-61 A Brief Syntax 61-66 A Treatment of the Arithmetic 66-74 A Note on the Written Language 74-75 In contrast Rodriguez' _Arte_, prepared under the influence of Alvarez' _Institutiones_, develops its description over the span of three books which treat both the spoken and written grammar in progressively greater detail. Thus: The Introduction iii-v BOOK I The Declensions 1-2v The Conjugations 2v-54 The Parts of Speech (_Rudimenta_) 55-80v BOOK II The Syntax of the Parts of Speech 83-168 Styles, Pronunciation, Poetics, etc. 168-184 BOOK III The Written Language 184v-206v Names, Titles, etc. 206v-212v The Arithmetic 212v-239 {12} Given these differing formats[10] it is clear that Collado is unable to cope adequately with the more complex aspects of the grammar, specifically those syntactic constructions to which Rodriguez devotes almost an entire book. An analysis of Collado's description and a listing of the portions of Rodriguez' grammar from which material was taken yields the following: _Collado_ _Rodriguez_ Phonology (3-5) {Parts of Speech (55-58) {Book III (173-179v) Nouns (6-13) {Declensions (1-2v) {Parts of Speech (59-61) Adjectives (9-11, 32-33) {Declensions (2-2v) {Conjugations (47-52) {Parts of Speech (61-67) Pronouns (13-18) {Declensions (2v) {Parts of Speech (67-68)